Unit - Freebase



and...


+ Do you know something that's missing from this view? Add it!
x Meter		The metre (meter in the US), symbol m, is the base unit of length in the International System of Units (SI). Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole (at sea level), its definition has...
x Kilogram		The kilogram or kilogramme (SI symbol: kg), also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram (IPK), which is almost exactly equal...
x Second		The second (SI unit symbol: s) is the International System of Units (SI) base unit of time and also a unit of time in other systems (abbreviated s or sec). Between 1000 (when al-Biruni used seconds) and 1960 the second was defined as 1/86,400 of a...
x Kelvin		The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units (SI) and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null...
x Metre per second		Metre per second (U.S. spelling: meter per second) is an SI derived unit of both speed (scalar) and velocity (vector quantity which specifies both magnitude and a specific direction), defined by distance in metres divided by time in seconds. The...
x Square meter		The square metre (British spelling) or square meter (American spelling) is the SI derived unit of area, with symbol m (33A1 in Unicode). It is defined as the area of a square whose sides measure exactly one metre. The square metre is derived from...
x Cubic metre		The cubic metre (US spelling: cubic meter, symbol: m) is the SI derived unit of volume. It is the volume of a cube with edges one metre in length. An alternative name, which allowed a different usage with metric prefixes, was the stère. Another...
x Joule		The joule ( /ˈdʒuːl/ or sometimes /ˈdʒaʊl/); symbol J) is a derived unit of energy or work in the International System of Units. It is equal to the energy expended (or work done) in applying a force of one newton through a distance of one meter (1...
x Pascal		The pascal (symbol: Pa) is the SI derived unit of pressure, internal pressure, stress, Young's modulus and tensile strength, named after the French mathematician, physicist, inventor, writer, and philosopher Blaise Pascal. It is a measure of force...
x Hour		The hour (common symbol: h or hr) is a unit of measurement of time. In modern usage, an hour comprises 60 minutes, or 3,600 seconds. It is approximately 1/24 of a mean solar day. An hour in the Universal Coordinated Time (UTC) time standard can...
x Day		A day is a unit of time, commonly defined as an interval equal to 24 hours. It also can mean that portion of the full day during which a location is illuminated by the light of the sun, also known as daytime. The period of time measured from local...
x Minute		A minute is a unit of measurement of time or of angle. The minute is a unit of time equal to 1/60 (the first sexagesimal fraction) of an hour or 60 seconds. In the UTC time scale, a minute on rare occasions has 59 or 61 seconds; see leap second. The...
x Kilometres per hour		The kilometre per hour (American English: kilometer per hour) (unit symbol km/h or km·h) is a unit of speed, expressing the number of kilometres travelled in one hour. Worldwide, the km/h is the most commonly used speed unit on road signs and car...
x Miles per hour		Miles per hour is an imperial unit of speed expressing the number of statute miles covered in one hour. It is currently the standard unit used for speed limits, and to express speeds generally, on roads in the United Kingdom and the United States....
x Watt		The watt ( /ˈwɒt/ WOT; symbol: W) is a derived unit of power in the International System of Units (SI), named after the Scottish engineer James Watt (1736–1819). The unit, defined as one joule per second, measures the rate of energy conversion or...
x Byte		The byte ( /ˈbaɪt/) is a unit of digital information in computing and telecommunications that most commonly consists of eight bits. Historically, a byte was the number of bits used to encode a single character of text in a computer and for this...
x Kilogram per cubic metre		Kilogram per cubic metre is an SI derived unit of density, defined by mass in kilograms divided by volume in cubic metres. The official SI symbolic abbreviation is kg·m, or equivalently either kg/m or . 1 kg·m is equivalent to: 1 g·cm = 1000 kg·m =...
x Newton		The newton (symbol: N) is the SI derived unit of force. It is named after Isaac Newton in recognition of his work on classical mechanics, specifically Newton's second law of motion. The newton is the SI unit for force; it is equal to the amount of...
x Gallon (US)		The gallon (abbreviation "gal"), with the US and imperial gallon, is a measure of volume. Historically it has had many definitions, but there are three definitions in current use: the imperial gallon (≈ 4.546 L) which since metrication is used...
x Liter		The litre (American spelling: liter; SI symbol l or L) is a non-SI metric system unit of volume equal to 1 cubic decimetre (dm), or 1,000 cubic centimetres (cm), or 1/1,000 cubic metre. If the lower case L is used as the symbol, it is sometimes...
x Pint (US)		The pint (abbreviated as "pt" or "p") is a unit of volume or capacity that was once used across much of Europe with values varying from state to state from less than half a litre to over one litre. Within continental Europe, the pint was replaced...
x Quart (US)		The quart is a unit of volume (for either the imperial or United States customary units) equal to a quarter of a gallon (hence the name quart), two pints, or four cups. Since gallons of various sizes have historically been in use, quarts of various...
x Fluid ounce (US)		A fluid ounce (abbreviated fl oz, fl. oz. or oz. fl.) is a unit of volume equal to about 28.4 ml in the imperial system or about 29.6 ml in the US system. The fluid ounce is distinct from the ounce, which measures mass. However, the fluid ounce is...
x Milliliter		A milliliter is a metric unit of volume that is 1/1000 of a liter. It is the same as a cubic centimeter.
x Gallon (Imperial)		The Imperial gallon was based on the volume of 10 lb. of distilled water weighed in air with brass weights with the barometer standing at 30 inches of mercury and at a temperature of 62 °F. In 1963, this definition was refined as the space occupied...
x Pint (Imperial)		The imperial pint is a unit of volume or capacity that is equivalent to 20 UK fluid ounces or 0.56826125 litres.
x Pound		The pound or pound-mass (abbreviations: lb, lbm, lbm, ℔ ) is a unit of mass used in the imperial, United States customary and other systems of measurement. A number of different definitions have been used, the most common today being the...
x Tonne		The tonne (SI unit symbol: t) is a metric system unit of mass equal to 1000 kilograms. It is a non-SI unit accepted for use with SI. To avoid confusion with the ton, it is also known as the metric tonne and metric ton in the United States and...
x Ounce		The ounce (abbreviated: oz, the old Italian word onza, now spelled oncia; apothecary symbol: ℥) is a unit of mass with several definitions, the most commonly used of which are equal to approximately 28 grams. The ounce is used in a number of...
x Long ton		Long ton (weight ton or imperial ton) is the name for the unit called the "ton" in the avoirdupois or Imperial system of measurements, as used in the United Kingdom and several other Commonwealth countries. One long ton is equal to 2,240 pounds (1...
x Short ton		The short ton is a unit of mass equal to 2,000 pounds (907.18474 kg). In the United States it is often called simply ton without distinguishing it from the metric ton (tonne, 1,000 kilograms / 2,204.62262 pounds) or the long ton (2,240 pounds / 1...
x Stone		The stone (abbreviation st) is a unit of measurement that was used in many North European countries until the advent of metrication. In the British Isles, it ceased to have legal status in 1986, but is still widely used informally to measure...
x Milligram		A milligram is a metric mass unit that is 1/1000th of a gram, or 1/1000000th of a kilogram.
x Gram		A Gram is a unit of measurement for mass (or weight). It is 1/1000th of a Kilogram.
x Microgram		A microgram is a Metric unit of weight that is 1/1000th of a milligram.
x Centimeter		A centimetre (American spelling: centimeter, symbol cm) is a unit of length in the metric system, equal to one hundredth of a metre, which is the SI base unit of length. Centi is the SI prefix for a factor of 10. Hence a centimetre can be written as...
x Inch		An inch (plural: inches; abbreviation or symbol: in or ″ – a double prime) is the name of a unit of length in a number of different systems, including Imperial units, and United States customary units. There are 36 inches in a yard and 12 inches in...
x Mile		A mile is a unit of length, most commonly 5,280 feet (1,760 yards, or about 1,609 metres). The mile of 5,280 feet is sometimes called the statute mile or land mile to distinguish it from the nautical mile (1,852 metres, about 6,076.1 feet). There...
x Micrometer		A micrometre (or micrometer) is by definition 1×10 of a metre (SI Standard prefix "micro" = 10). In plain English, it means one-millionth of a metre (or one-thousandth of a millimetre, 0.001 mm, or about 0.000039 inches). Its unit symbol in the...
x Yard		A yard (abbreviation: yd) is a unit of length in several different systems including United States customary units, Imperial units and the former English units. It is equal to 3 feet or 36 inches. Under an agreement in 1959 between Australia, Canada...
x Kilometer		The kilometre (American spelling: kilometer; SI symbol: km) is a unit of length in the metric system, equal to one thousand metres (kilo- being the SI prefix for 1000). It is now the measurement unit used officially for expressing distances between...
x Millimeter		The millimetre (American spelling: millimeter; SI unit symbol mm; informal abbreviation: mil) is a unit of length in the metric system, equal to one thousandth of a metre, which is the SI base unit of length. It is equal to 1,000 micrometres and 1...
x Ångström		The angstrom or ångström /ˈæŋstrəm/ is a unit of length equal to 1/10,000,000,000 (one ten billionth) of a meter (1×10 m or 100 pm). Its symbol is the Swedish letter Å. The angstrom is often used in the natural sciences and technology to express...
x Foot		A foot (plural: feet; abbreviation or symbol: ft or ′ (the prime symbol)) is a unit of length defined as being 0.3048 m exactly and used in the imperial system of units and United States customary units. It is subdivided into 12 inches. Historically...
x Hectare		The hectare ( /ˈhɛktɛər/ or /ˈhɛktɑr/; symbol ha) is a metric unit of area defined as 10,000 square metres (100 m by 100 m), and primarily used in the measurement of land. In 1795, when the metric system was introduced, the 'are' was defined as...
x Square kilometer		Square kilometer, symbol km, is a decimal multiple of the SI unit of surface area, the square metre, one of the SI derived units. 1 km is equal to: Conversely: 2.47 acres/ha Note: "km" means (km), square kilometre or kilometre squared and not k(m),...
x Square mile		The square mile (abbreviated as sq mi and sometimes as mi) is an imperial and US unit of measure for an area equal to the area of a square of one statute mile. It should not be confused with miles square, which refers to the number of miles on each...
x Square yard		The square yard is an imperial/US customary (non-metric) unit of area, formerly used in most of the English-speaking world but now generally replaced by the square metre outside of the U.S., Canada and the U.K. It is defined as the area of a square...
x Degree Celsius		Celsius, formerly known as centigrade, is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius (1701–1744), who developed a similar temperature scale. The degree Celsius (°C) can refer to a...
x Degree Fahrenheit		Fahrenheit is the temperature scale proposed in 1724 by, and named after, the physicist Daniel Gabriel Fahrenheit (1686–1736). Within this scale, the freezing of water into ice is defined at 32 degrees, while the boiling point of water is defined to...
x Degree Rankine		Rankine is a thermodynamic (absolute) temperature scale named after the Glasgow University engineer and physicist William John Macquorn Rankine, who proposed it in 1859. (The Kelvin scale was first proposed in 1848.) The symbol for degrees Rankine...
x Calorie		The calorie is a pre-SI metric unit of energy. It was first defined by Nicolas Clément in 1824 as a unit of heat, entering French and English dictionaries between 1841 and 1867. In most fields its use is archaic, having been replaced by the SI unit...
x Watt-hour		The kilowatt hour, or kilowatt-hour, (symbol kW·h, kW h or kWh) is a unit of energy equal to 1000 watt hours or 3.6 megajoules. For constant power, energy in watt hours is the product of power in watts and time in hours. The kilowatt hour is most...
x Pound-force per square inch		The pound per square inch or, more accurately, pound-force per square inch (symbol: psi or lbf/in² or lbf/in²) is a unit of pressure or of stress based on avoirdupois units. It is the pressure resulting from a force of one pound-force applied to an...
x Torr		The torr (symbol: Torr) is a non-SI unit of pressure with the ratio of 760 to 1 standard atmosphere, chosen to be roughly equal to the fluid pressure exerted by a millimeter of mercury, i.e., a pressure of 1 Torr is approximately equal to one...
x Bar		The bar is a unit of pressure defined as 1,000,000 dynes per square centimetre (or equivalently in SI units, 100 kilopascals, or in CGS units, 1 megabarye). It is about equal to the atmospheric pressure on Earth at sea level. Other units derived...
x Atmosphere		The standard atmosphere (symbol: atm) is an international reference pressure defined as 101325 Pa and formerly used as unit of pressure. For practical purposes it has been replaced by the bar which is 10 Pa. The difference of about 1% is not...
x Mechanical horsepower		The term horsepower was invented by the engineer James Watt in 1782. Watt (1736 to 1819) is most famous for his work on improving the performance of steam engines. Watt was working with ponies lifting coal at a coal mine, and he wanted to define the...
x Metric horsepower		Metric horsepower began in Germany in the 19th century and became popular across Europe and Asia. The various units used to indicate this definition ("PS", "CV", "pk", and "ch") all translate to "horse power" in English, so it is common to see these...
x Boiler horsepower		(From Wikipedia, “Horsepower.”)

x Meter

The metre (meter in the US), symbol m, is the base unit of length in the International System of Units (SI). Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole (at sea level), its definition has...

x Kilogram

The kilogram or kilogramme (SI symbol: kg), also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram (IPK), which is almost exactly equal...

x Second

The second (SI unit symbol: s) is the International System of Units (SI) base unit of time and also a unit of time in other systems (abbreviated s or sec). Between 1000 (when al-Biruni used seconds) and 1960 the second was defined as 1/86,400 of a...

x Kelvin

The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units (SI) and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null...

x Metre per second

Metre per second (U.S. spelling: meter per second) is an SI derived unit of both speed (scalar) and velocity (vector quantity which specifies both magnitude and a specific direction), defined by distance in metres divided by time in seconds. The...

x Square meter

The square metre (British spelling) or square meter (American spelling) is the SI derived unit of area, with symbol m (33A1 in Unicode). It is defined as the area of a square whose sides measure exactly one metre. The square metre is derived from...

x Cubic metre

The cubic metre (US spelling: cubic meter, symbol: m) is the SI derived unit of volume. It is the volume of a cube with edges one metre in length. An alternative name, which allowed a different usage with metric prefixes, was the stère. Another...

x Joule

The joule ( /ˈdʒuːl/ or sometimes /ˈdʒaʊl/); symbol J) is a derived unit of energy or work in the International System of Units. It is equal to the energy expended (or work done) in applying a force of one newton through a distance of one meter (1...

x Pascal

The pascal (symbol: Pa) is the SI derived unit of pressure, internal pressure, stress, Young's modulus and tensile strength, named after the French mathematician, physicist, inventor, writer, and philosopher Blaise Pascal. It is a measure of force...

x Hour

The hour (common symbol: h or hr) is a unit of measurement of time. In modern usage, an hour comprises 60 minutes, or 3,600 seconds. It is approximately 1/24 of a mean solar day. An hour in the Universal Coordinated Time (UTC) time standard can...

x Day

A day is a unit of time, commonly defined as an interval equal to 24 hours. It also can mean that portion of the full day during which a location is illuminated by the light of the sun, also known as daytime. The period of time measured from local...

x Minute

A minute is a unit of measurement of time or of angle. The minute is a unit of time equal to 1/60 (the first sexagesimal fraction) of an hour or 60 seconds. In the UTC time scale, a minute on rare occasions has 59 or 61 seconds; see leap second. The...

x Kilometres per hour

The kilometre per hour (American English: kilometer per hour) (unit symbol km/h or km·h) is a unit of speed, expressing the number of kilometres travelled in one hour. Worldwide, the km/h is the most commonly used speed unit on road signs and car...

x Miles per hour

Miles per hour is an imperial unit of speed expressing the number of statute miles covered in one hour. It is currently the standard unit used for speed limits, and to express speeds generally, on roads in the United Kingdom and the United States....

x Watt

The watt ( /ˈwɒt/ WOT; symbol: W) is a derived unit of power in the International System of Units (SI), named after the Scottish engineer James Watt (1736–1819). The unit, defined as one joule per second, measures the rate of energy conversion or...

x Byte

The byte ( /ˈbaɪt/) is a unit of digital information in computing and telecommunications that most commonly consists of eight bits. Historically, a byte was the number of bits used to encode a single character of text in a computer and for this...

x Kilogram per cubic metre

Kilogram per cubic metre is an SI derived unit of density, defined by mass in kilograms divided by volume in cubic metres. The official SI symbolic abbreviation is kg·m, or equivalently either kg/m or . 1 kg·m is equivalent to: 1 g·cm = 1000 kg·m =...

x Newton

The newton (symbol: N) is the SI derived unit of force. It is named after Isaac Newton in recognition of his work on classical mechanics, specifically Newton's second law of motion. The newton is the SI unit for force; it is equal to the amount of...

x Gallon (US)

The gallon (abbreviation "gal"), with the US and imperial gallon, is a measure of volume. Historically it has had many definitions, but there are three definitions in current use: the imperial gallon (≈ 4.546 L) which since metrication is used...

x Liter

The litre (American spelling: liter; SI symbol l or L) is a non-SI metric system unit of volume equal to 1 cubic decimetre (dm), or 1,000 cubic centimetres (cm), or 1/1,000 cubic metre. If the lower case L is used as the symbol, it is sometimes...

x Pint (US)

The pint (abbreviated as "pt" or "p") is a unit of volume or capacity that was once used across much of Europe with values varying from state to state from less than half a litre to over one litre. Within continental Europe, the pint was replaced...

x Quart (US)

The quart is a unit of volume (for either the imperial or United States customary units) equal to a quarter of a gallon (hence the name quart), two pints, or four cups. Since gallons of various sizes have historically been in use, quarts of various...

x Fluid ounce (US)

A fluid ounce (abbreviated fl oz, fl. oz. or oz. fl.) is a unit of volume equal to about 28.4 ml in the imperial system or about 29.6 ml in the US system. The fluid ounce is distinct from the ounce, which measures mass. However, the fluid ounce is...

x Milliliter

A milliliter is a metric unit of volume that is 1/1000 of a liter. It is the same as a cubic centimeter.

x Gallon (Imperial)

The Imperial gallon was based on the volume of 10 lb. of distilled water weighed in air with brass weights with the barometer standing at 30 inches of mercury and at a temperature of 62 °F. In 1963, this definition was refined as the space occupied...

x Pint (Imperial)

The imperial pint is a unit of volume or capacity that is equivalent to 20 UK fluid ounces or 0.56826125 litres.

x Pound

The pound or pound-mass (abbreviations: lb, lbm, lbm, ℔ ) is a unit of mass used in the imperial, United States customary and other systems of measurement. A number of different definitions have been used, the most common today being the...

x Tonne

The tonne (SI unit symbol: t) is a metric system unit of mass equal to 1000 kilograms. It is a non-SI unit accepted for use with SI. To avoid confusion with the ton, it is also known as the metric tonne and metric ton in the United States and...

x Ounce

The ounce (abbreviated: oz, the old Italian word onza, now spelled oncia; apothecary symbol: ℥) is a unit of mass with several definitions, the most commonly used of which are equal to approximately 28 grams. The ounce is used in a number of...

x Long ton

Long ton (weight ton or imperial ton) is the name for the unit called the "ton" in the avoirdupois or Imperial system of measurements, as used in the United Kingdom and several other Commonwealth countries. One long ton is equal to 2,240 pounds (1...

x Short ton

The short ton is a unit of mass equal to 2,000 pounds (907.18474 kg). In the United States it is often called simply ton without distinguishing it from the metric ton (tonne, 1,000 kilograms / 2,204.62262 pounds) or the long ton (2,240 pounds / 1...

x Stone

The stone (abbreviation st) is a unit of measurement that was used in many North European countries until the advent of metrication. In the British Isles, it ceased to have legal status in 1986, but is still widely used informally to measure...

x Milligram

A milligram is a metric mass unit that is 1/1000th of a gram, or 1/1000000th of a kilogram.

x Gram

A Gram is a unit of measurement for mass (or weight). It is 1/1000th of a Kilogram.

x Microgram

A microgram is a Metric unit of weight that is 1/1000th of a milligram.

x Centimeter

A centimetre (American spelling: centimeter, symbol cm) is a unit of length in the metric system, equal to one hundredth of a metre, which is the SI base unit of length. Centi is the SI prefix for a factor of 10. Hence a centimetre can be written as...

x Inch

An inch (plural: inches; abbreviation or symbol: in or ″ – a double prime) is the name of a unit of length in a number of different systems, including Imperial units, and United States customary units. There are 36 inches in a yard and 12 inches in...

x Mile

A mile is a unit of length, most commonly 5,280 feet (1,760 yards, or about 1,609 metres). The mile of 5,280 feet is sometimes called the statute mile or land mile to distinguish it from the nautical mile (1,852 metres, about 6,076.1 feet). There...

x Micrometer

A micrometre (or micrometer) is by definition 1×10 of a metre (SI Standard prefix "micro" = 10). In plain English, it means one-millionth of a metre (or one-thousandth of a millimetre, 0.001 mm, or about 0.000039 inches). Its unit symbol in the...

x Yard

A yard (abbreviation: yd) is a unit of length in several different systems including United States customary units, Imperial units and the former English units. It is equal to 3 feet or 36 inches. Under an agreement in 1959 between Australia, Canada...

x Kilometer

The kilometre (American spelling: kilometer; SI symbol: km) is a unit of length in the metric system, equal to one thousand metres (kilo- being the SI prefix for 1000). It is now the measurement unit used officially for expressing distances between...

x Millimeter

The millimetre (American spelling: millimeter; SI unit symbol mm; informal abbreviation: mil) is a unit of length in the metric system, equal to one thousandth of a metre, which is the SI base unit of length. It is equal to 1,000 micrometres and 1...

x Ångström

The angstrom or ångström /ˈæŋstrəm/ is a unit of length equal to 1/10,000,000,000 (one ten billionth) of a meter (1×10 m or 100 pm). Its symbol is the Swedish letter Å. The angstrom is often used in the natural sciences and technology to express...

x Foot

A foot (plural: feet; abbreviation or symbol: ft or ′ (the prime symbol)) is a unit of length defined as being 0.3048 m exactly and used in the imperial system of units and United States customary units. It is subdivided into 12 inches. Historically...

x Hectare

The hectare ( /ˈhɛktɛər/ or /ˈhɛktɑr/; symbol ha) is a metric unit of area defined as 10,000 square metres (100 m by 100 m), and primarily used in the measurement of land. In 1795, when the metric system was introduced, the 'are' was defined as...

x Square kilometer

Square kilometer, symbol km, is a decimal multiple of the SI unit of surface area, the square metre, one of the SI derived units. 1 km is equal to: Conversely: 2.47 acres/ha Note: "km" means (km), square kilometre or kilometre squared and not k(m),...

x Square mile

The square mile (abbreviated as sq mi and sometimes as mi) is an imperial and US unit of measure for an area equal to the area of a square of one statute mile. It should not be confused with miles square, which refers to the number of miles on each...

x Square yard

The square yard is an imperial/US customary (non-metric) unit of area, formerly used in most of the English-speaking world but now generally replaced by the square metre outside of the U.S., Canada and the U.K. It is defined as the area of a square...

x Degree Celsius

Celsius, formerly known as centigrade, is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius (1701–1744), who developed a similar temperature scale. The degree Celsius (°C) can refer to a...

x Degree Fahrenheit

Fahrenheit is the temperature scale proposed in 1724 by, and named after, the physicist Daniel Gabriel Fahrenheit (1686–1736). Within this scale, the freezing of water into ice is defined at 32 degrees, while the boiling point of water is defined to...

x Degree Rankine

Rankine is a thermodynamic (absolute) temperature scale named after the Glasgow University engineer and physicist William John Macquorn Rankine, who proposed it in 1859. (The Kelvin scale was first proposed in 1848.) The symbol for degrees Rankine...

x Calorie

The calorie is a pre-SI metric unit of energy. It was first defined by Nicolas Clément in 1824 as a unit of heat, entering French and English dictionaries between 1841 and 1867. In most fields its use is archaic, having been replaced by the SI unit...

x Watt-hour

The kilowatt hour, or kilowatt-hour, (symbol kW·h, kW h or kWh) is a unit of energy equal to 1000 watt hours or 3.6 megajoules. For constant power, energy in watt hours is the product of power in watts and time in hours. The kilowatt hour is most...

x Pound-force per square inch

The pound per square inch or, more accurately, pound-force per square inch (symbol: psi or lbf/in² or lbf/in²) is a unit of pressure or of stress based on avoirdupois units. It is the pressure resulting from a force of one pound-force applied to an...

x Torr

The torr (symbol: Torr) is a non-SI unit of pressure with the ratio of 760 to 1 standard atmosphere, chosen to be roughly equal to the fluid pressure exerted by a millimeter of mercury, i.e., a pressure of 1 Torr is approximately equal to one...

x Bar

The bar is a unit of pressure defined as 1,000,000 dynes per square centimetre (or equivalently in SI units, 100 kilopascals, or in CGS units, 1 megabarye). It is about equal to the atmospheric pressure on Earth at sea level. Other units derived...

x Atmosphere

The standard atmosphere (symbol: atm) is an international reference pressure defined as 101325 Pa and formerly used as unit of pressure. For practical purposes it has been replaced by the bar which is 10 Pa. The difference of about 1% is not...

x Mechanical horsepower

The term horsepower was invented by the engineer James Watt in 1782. Watt (1736 to 1819) is most famous for his work on improving the performance of steam engines. Watt was working with ponies lifting coal at a coal mine, and he wanted to define the...

x Metric horsepower

Metric horsepower began in Germany in the 19th century and became popular across Europe and Asia. The various units used to indicate this definition ("PS", "CV", "pk", and "ch") all translate to "horse power" in English, so it is common to see these...

x Boiler horsepower

(From Wikipedia, “Horsepower.”)

Unit Filter Unit topics

about 600 Unit topics matching:

x Add new column Show in info bubble Show in info bubble Add new edge

Do you know something that's missing from this view? Add it!

Edit Collection Schema

All topics in this collection are typed as Unit

Use Data from this Collection

Choose a format:

Flag this Collection

Why do you want to flag this collection?


x name	x image	x article
+ Do you know something that's missing from this view? Add it!
x Meter		The metre (meter in the US), symbol m, is the base unit of length in the International System of Units (SI). Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole (at sea level), its definition has...
x Kilogram		The kilogram or kilogramme (SI symbol: kg), also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram (IPK), which is almost exactly equal...
x Second		The second (SI unit symbol: s) is the International System of Units (SI) base unit of time and also a unit of time in other systems (abbreviated s or sec). Between 1000 (when al-Biruni used seconds) and 1960 the second was defined as 1/86,400 of a...
x Kelvin		The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units (SI) and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null...
x Metre per second		Metre per second (U.S. spelling: meter per second) is an SI derived unit of both speed (scalar) and velocity (vector quantity which specifies both magnitude and a specific direction), defined by distance in metres divided by time in seconds. The...
x Square meter		The square metre (British spelling) or square meter (American spelling) is the SI derived unit of area, with symbol m (33A1 in Unicode). It is defined as the area of a square whose sides measure exactly one metre. The square metre is derived from...
x Cubic metre		The cubic metre (US spelling: cubic meter, symbol: m) is the SI derived unit of volume. It is the volume of a cube with edges one metre in length. An alternative name, which allowed a different usage with metric prefixes, was the stère. Another...
x Joule		The joule ( /ˈdʒuːl/ or sometimes /ˈdʒaʊl/); symbol J) is a derived unit of energy or work in the International System of Units. It is equal to the energy expended (or work done) in applying a force of one newton through a distance of one meter (1...
x Pascal		The pascal (symbol: Pa) is the SI derived unit of pressure, internal pressure, stress, Young's modulus and tensile strength, named after the French mathematician, physicist, inventor, writer, and philosopher Blaise Pascal. It is a measure of force...
x Hour		The hour (common symbol: h or hr) is a unit of measurement of time. In modern usage, an hour comprises 60 minutes, or 3,600 seconds. It is approximately 1/24 of a mean solar day. An hour in the Universal Coordinated Time (UTC) time standard can...
x Day		A day is a unit of time, commonly defined as an interval equal to 24 hours. It also can mean that portion of the full day during which a location is illuminated by the light of the sun, also known as daytime. The period of time measured from local...
x Minute		A minute is a unit of measurement of time or of angle. The minute is a unit of time equal to 1/60 (the first sexagesimal fraction) of an hour or 60 seconds. In the UTC time scale, a minute on rare occasions has 59 or 61 seconds; see leap second. The...
x Kilometres per hour		The kilometre per hour (American English: kilometer per hour) (unit symbol km/h or km·h) is a unit of speed, expressing the number of kilometres travelled in one hour. Worldwide, the km/h is the most commonly used speed unit on road signs and car...
x Miles per hour		Miles per hour is an imperial unit of speed expressing the number of statute miles covered in one hour. It is currently the standard unit used for speed limits, and to express speeds generally, on roads in the United Kingdom and the United States....
x Watt		The watt ( /ˈwɒt/ WOT; symbol: W) is a derived unit of power in the International System of Units (SI), named after the Scottish engineer James Watt (1736–1819). The unit, defined as one joule per second, measures the rate of energy conversion or...
x Byte		The byte ( /ˈbaɪt/) is a unit of digital information in computing and telecommunications that most commonly consists of eight bits. Historically, a byte was the number of bits used to encode a single character of text in a computer and for this...
x Kilogram per cubic metre		Kilogram per cubic metre is an SI derived unit of density, defined by mass in kilograms divided by volume in cubic metres. The official SI symbolic abbreviation is kg·m, or equivalently either kg/m or . 1 kg·m is equivalent to: 1 g·cm = 1000 kg·m =...
x Newton		The newton (symbol: N) is the SI derived unit of force. It is named after Isaac Newton in recognition of his work on classical mechanics, specifically Newton's second law of motion. The newton is the SI unit for force; it is equal to the amount of...
x Gallon (US)		The gallon (abbreviation "gal"), with the US and imperial gallon, is a measure of volume. Historically it has had many definitions, but there are three definitions in current use: the imperial gallon (≈ 4.546 L) which since metrication is used...
x Liter		The litre (American spelling: liter; SI symbol l or L) is a non-SI metric system unit of volume equal to 1 cubic decimetre (dm), or 1,000 cubic centimetres (cm), or 1/1,000 cubic metre. If the lower case L is used as the symbol, it is sometimes...
x Pint (US)		The pint (abbreviated as "pt" or "p") is a unit of volume or capacity that was once used across much of Europe with values varying from state to state from less than half a litre to over one litre. Within continental Europe, the pint was replaced...
x Quart (US)		The quart is a unit of volume (for either the imperial or United States customary units) equal to a quarter of a gallon (hence the name quart), two pints, or four cups. Since gallons of various sizes have historically been in use, quarts of various...
x Fluid ounce (US)		A fluid ounce (abbreviated fl oz, fl. oz. or oz. fl.) is a unit of volume equal to about 28.4 ml in the imperial system or about 29.6 ml in the US system. The fluid ounce is distinct from the ounce, which measures mass. However, the fluid ounce is...
x Milliliter		A milliliter is a metric unit of volume that is 1/1000 of a liter. It is the same as a cubic centimeter.
x Gallon (Imperial)		The Imperial gallon was based on the volume of 10 lb. of distilled water weighed in air with brass weights with the barometer standing at 30 inches of mercury and at a temperature of 62 °F. In 1963, this definition was refined as the space occupied...
x Pint (Imperial)		The imperial pint is a unit of volume or capacity that is equivalent to 20 UK fluid ounces or 0.56826125 litres.
x Pound		The pound or pound-mass (abbreviations: lb, lbm, lbm, ℔ ) is a unit of mass used in the imperial, United States customary and other systems of measurement. A number of different definitions have been used, the most common today being the...
x Tonne		The tonne (SI unit symbol: t) is a metric system unit of mass equal to 1000 kilograms. It is a non-SI unit accepted for use with SI. To avoid confusion with the ton, it is also known as the metric tonne and metric ton in the United States and...
x Ounce		The ounce (abbreviated: oz, the old Italian word onza, now spelled oncia; apothecary symbol: ℥) is a unit of mass with several definitions, the most commonly used of which are equal to approximately 28 grams. The ounce is used in a number of...
x Long ton		Long ton (weight ton or imperial ton) is the name for the unit called the "ton" in the avoirdupois or Imperial system of measurements, as used in the United Kingdom and several other Commonwealth countries. One long ton is equal to 2,240 pounds (1...
x Short ton		The short ton is a unit of mass equal to 2,000 pounds (907.18474 kg). In the United States it is often called simply ton without distinguishing it from the metric ton (tonne, 1,000 kilograms / 2,204.62262 pounds) or the long ton (2,240 pounds / 1...
x Stone		The stone (abbreviation st) is a unit of measurement that was used in many North European countries until the advent of metrication. In the British Isles, it ceased to have legal status in 1986, but is still widely used informally to measure...
x Milligram		A milligram is a metric mass unit that is 1/1000th of a gram, or 1/1000000th of a kilogram.
x Gram		A Gram is a unit of measurement for mass (or weight). It is 1/1000th of a Kilogram.
x Microgram		A microgram is a Metric unit of weight that is 1/1000th of a milligram.
x Centimeter		A centimetre (American spelling: centimeter, symbol cm) is a unit of length in the metric system, equal to one hundredth of a metre, which is the SI base unit of length. Centi is the SI prefix for a factor of 10. Hence a centimetre can be written as...
x Inch		An inch (plural: inches; abbreviation or symbol: in or ″ – a double prime) is the name of a unit of length in a number of different systems, including Imperial units, and United States customary units. There are 36 inches in a yard and 12 inches in...
x Mile		A mile is a unit of length, most commonly 5,280 feet (1,760 yards, or about 1,609 metres). The mile of 5,280 feet is sometimes called the statute mile or land mile to distinguish it from the nautical mile (1,852 metres, about 6,076.1 feet). There...
x Micrometer		A micrometre (or micrometer) is by definition 1×10 of a metre (SI Standard prefix "micro" = 10). In plain English, it means one-millionth of a metre (or one-thousandth of a millimetre, 0.001 mm, or about 0.000039 inches). Its unit symbol in the...
x Yard		A yard (abbreviation: yd) is a unit of length in several different systems including United States customary units, Imperial units and the former English units. It is equal to 3 feet or 36 inches. Under an agreement in 1959 between Australia, Canada...
x Kilometer		The kilometre (American spelling: kilometer; SI symbol: km) is a unit of length in the metric system, equal to one thousand metres (kilo- being the SI prefix for 1000). It is now the measurement unit used officially for expressing distances between...
x Millimeter		The millimetre (American spelling: millimeter; SI unit symbol mm; informal abbreviation: mil) is a unit of length in the metric system, equal to one thousandth of a metre, which is the SI base unit of length. It is equal to 1,000 micrometres and 1...
x Ångström		The angstrom or ångström /ˈæŋstrəm/ is a unit of length equal to 1/10,000,000,000 (one ten billionth) of a meter (1×10 m or 100 pm). Its symbol is the Swedish letter Å. The angstrom is often used in the natural sciences and technology to express...
x Foot		A foot (plural: feet; abbreviation or symbol: ft or ′ (the prime symbol)) is a unit of length defined as being 0.3048 m exactly and used in the imperial system of units and United States customary units. It is subdivided into 12 inches. Historically...
x Hectare		The hectare ( /ˈhɛktɛər/ or /ˈhɛktɑr/; symbol ha) is a metric unit of area defined as 10,000 square metres (100 m by 100 m), and primarily used in the measurement of land. In 1795, when the metric system was introduced, the 'are' was defined as...
x Square kilometer		Square kilometer, symbol km, is a decimal multiple of the SI unit of surface area, the square metre, one of the SI derived units. 1 km is equal to: Conversely: 2.47 acres/ha Note: "km" means (km), square kilometre or kilometre squared and not k(m),...
x Square mile		The square mile (abbreviated as sq mi and sometimes as mi) is an imperial and US unit of measure for an area equal to the area of a square of one statute mile. It should not be confused with miles square, which refers to the number of miles on each...
x Square yard		The square yard is an imperial/US customary (non-metric) unit of area, formerly used in most of the English-speaking world but now generally replaced by the square metre outside of the U.S., Canada and the U.K. It is defined as the area of a square...
x Degree Celsius		Celsius, formerly known as centigrade, is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius (1701–1744), who developed a similar temperature scale. The degree Celsius (°C) can refer to a...
x Degree Fahrenheit		Fahrenheit is the temperature scale proposed in 1724 by, and named after, the physicist Daniel Gabriel Fahrenheit (1686–1736). Within this scale, the freezing of water into ice is defined at 32 degrees, while the boiling point of water is defined to...
x Degree Rankine		Rankine is a thermodynamic (absolute) temperature scale named after the Glasgow University engineer and physicist William John Macquorn Rankine, who proposed it in 1859. (The Kelvin scale was first proposed in 1848.) The symbol for degrees Rankine...
x Calorie		The calorie is a pre-SI metric unit of energy. It was first defined by Nicolas Clément in 1824 as a unit of heat, entering French and English dictionaries between 1841 and 1867. In most fields its use is archaic, having been replaced by the SI unit...
x Watt-hour		The kilowatt hour, or kilowatt-hour, (symbol kW·h, kW h or kWh) is a unit of energy equal to 1000 watt hours or 3.6 megajoules. For constant power, energy in watt hours is the product of power in watts and time in hours. The kilowatt hour is most...
x Pound-force per square inch		The pound per square inch or, more accurately, pound-force per square inch (symbol: psi or lbf/in² or lbf/in²) is a unit of pressure or of stress based on avoirdupois units. It is the pressure resulting from a force of one pound-force applied to an...
x Torr		The torr (symbol: Torr) is a non-SI unit of pressure with the ratio of 760 to 1 standard atmosphere, chosen to be roughly equal to the fluid pressure exerted by a millimeter of mercury, i.e., a pressure of 1 Torr is approximately equal to one...
x Bar		The bar is a unit of pressure defined as 1,000,000 dynes per square centimetre (or equivalently in SI units, 100 kilopascals, or in CGS units, 1 megabarye). It is about equal to the atmospheric pressure on Earth at sea level. Other units derived...
x Atmosphere		The standard atmosphere (symbol: atm) is an international reference pressure defined as 101325 Pa and formerly used as unit of pressure. For practical purposes it has been replaced by the bar which is 10 Pa. The difference of about 1% is not...
x Mechanical horsepower		The term horsepower was invented by the engineer James Watt in 1782. Watt (1736 to 1819) is most famous for his work on improving the performance of steam engines. Watt was working with ponies lifting coal at a coal mine, and he wanted to define the...
x Metric horsepower		Metric horsepower began in Germany in the 19th century and became popular across Europe and Asia. The various units used to indicate this definition ("PS", "CV", "pk", and "ch") all translate to "horse power" in English, so it is common to see these...
x Boiler horsepower		(From Wikipedia, “Horsepower.”)