Unit Reference

Angles

Symbol	Name	Definition
° or degree or degrees	Degrees	A unit of angular measurement, where a full circle is 360 degrees
rad or radian or radians	Radians	The angle subtended at the center of a circle by an arc whose length is equal to the radius of the circle

Area

Symbol	Name	Definition
m² or square meter or square meters or sq m	Square Meter	The SI unit of area, defined as the area of a square with sides one meter long.
cm² or square centimeter or square centimeters or sq cm	Square Centimeter	A unit of area equal to one ten-thousandth of a square meter.
in² or square inch or square inches or sq in	Square Inch	A unit of area in the imperial and US customary systems, equal to the area of a square with sides one inch long.
ft² or square foot or square feet or sq ft	Square Foot	A unit of area in the imperial and US customary systems, equal to the area of a square with sides one foot long.
ft²US or square footUS or square feetUS or sq ftUS	Square Foot (US)	A specific variant of the square foot used in the US customary system.
mm² or square millimeter or square millimeters or sq mm	Square Millimeter	A unit of area equal to one millionth of a square meter.
ha or hectare or hectares	Hectare	A metric unit of area, equal to 10,000 square meters, commonly used for land measurement.
km² or square kilometer or square kilometers or sq km or square km	Square Kilometer	A unit of area equal to one million square meters, used for larger land areas.
yd² or square yard or square yards or sq yd	Square Yard	A unit of area in the imperial and US customary systems, equal to the area of a square with sides one yard long.
mi² or square mile or square miles or sq mi	Square Mile	A unit of area in the imperial and US customary systems, equal to the area of a square with sides one mile long, often used for very large land areas.
ac or acre or acres	Acre	A unit of land area, typically used in the imperial and US customary systems, historically defined as the area a pair of oxen could plow in a day.
area or areas	Are	A metric unit of area, equal to 100 square meters (10 meters by 10 meters), less commonly used than the hectare.

Digital Data

Symbol	Name	Definition
b or bit or bits	Bit	The fundamental unit of information, representing a binary value (0 or 1).
kb or kilobit or kilobits	Kilobit	A unit of digital information equal to 1,000 bits (10^3 bits).
Mb or megabit or megabits	Megabit	A unit of digital information equal to 1,000,000 bits (10^6 bits).
Gb or gigabit or gigabits	Gigabit	A unit of digital information equal to 1,000,000,000 bits (10^9 bits).
Tb or terabit or terabits	Terabit	A unit of digital information equal to 1,000,000,000,000 bits (10^12 bits).
Pb or petabit or petabits	Petabit	A unit of digital information equal to 1,000,000,000,000,000 bits (10^15 bits).
Eb or exabit or exabits	Exabit	A unit of digital information equal to 1,000,000,000,000,000,000 bits (10^18 bits).
Kibit or kibibit or kibibits	Kibibit	A unit of digital information equal to 1,024 bits (2^10 bits).
Mibit or mebibit or mebibits	Mebibit	A unit of digital information equal to 1,048,576 bits (2^20 bits).
Gibit or gibibit or gibibits	Gibibit	A unit of digital information equal to 1,073,741,824 bits (2^30 bits).
Tibit or tebibit or tebibits	Tebibit	A unit of digital information equal to 1,099,511,627,776 bits (2^40 bits).
Pibit or pebibit or pebibits	Pebibit	A unit of digital information equal to 1,125,899,906,842,624 bits (2^50 bits).
Eibit or exbibit or exbibits	Exbibit	A unit of digital information equal to 1,152,921,504,606,846,976 bits (2^60 bits).
B or byte or bytes	Byte	A unit of digital information typically consisting of 8 bits.
kB or kilobyte or kilobytes	Kilobyte	A unit of digital information equal to 1,000 bytes (10^3 bytes).
MB or megabyte or megabytes	Megabyte	A unit of digital information equal to 1,000,000 bytes (10^6 bytes).
GB or gigabyte or gigabytes	Gigabyte	A unit of digital information equal to 1,000,000,000 bytes (10^9 bytes).
TB or terabyte or terabytes	Terabyte	A unit of digital information equal to 1,000,000,000,000 bytes (10^12 bytes).
PB or petabyte or petabytes	Petabyte	A unit of digital information equal to 1,000,000,000,000,000 bytes (10^15 bytes).
EB or exabyte or exabytes	Exabyte	A unit of digital information equal to 1,000,000,000,000,000,000 bytes (10^18 bytes).
KiB or kibibyte or kibibytes	Kibibyte	A unit of digital information equal to 1,024 bytes (2^10 bytes).
MiB or mebibyte or mebibytes	Mebibyte	A unit of digital information equal to 1,048,576 bytes (2^20 bytes).
GiB or gibibyte or gibibytes	Gibibyte	A unit of digital information equal to 1,073,741,824 bytes (2^30 bytes).
TiB or tebibyte or tebibytes	Tebibyte	A unit of digital information equal to 1,099,511,627,776 bytes (2^40 bytes).
PiB or pebibyte or pebibytes	Pebibyte	A unit of digital information equal to 1,125,899,906,842,624 bytes (2^50 bytes).
EiB or exbibyte or exbibytes	Exbibyte	A unit of digital information equal to 1,152,921,504,606,846,976 bytes (2^60 bytes).

Forces

Symbol	Name	Definition
N or newtons	Newton	The SI unit of force, defined as the force required to accelerate a mass of one kilogram at a rate of one meter per second squared.
dyn	Dyne	A unit of force in the centimetre-gram-second (CGS) system, equal to 10^-5 newtons.
lbf or pound force	Pound-force	A unit of force in the imperial and US customary systems, defined as the gravitational force exerted on a mass of one pound.
kgf or kilogram force	Kilogram-force	A unit of force equal to the magnitude of the force exerted by gravity on one kilogram of mass (approximately 9,80665 newtons).
pdl	Poundal	A unit of force in the foot-pound-second (FPS) system, defined as the force required to accelerate a mass of one pound at a rate of one foot per second squared.

Fuels

Symbol	Name	Definition
km/l or kilometers per liter	Kilometers per Liter	A measure of fuel efficiency, indicating the distance in kilometers traveled per liter of fuel consumed.
l/100km or liters per 100 km	Liters per 100 km	A measure of fuel consumption, indicating the volume of fuel in liters consumed to travel 100 kilometers.
mpgUS or miles per US gallon	Miles per US Gallon	A measure of fuel efficiency, indicating the distance in miles traveled per US gallon of fuel consumed.
mpg or miles per Imperial gallon	Miles per Imperial Gallon	A measure of fuel efficiency, indicating the distance in miles traveled per Imperial gallon of fuel consumed.

Lengths

Symbol	Name	Definition
m or metre or metres or meter or meters	Meters	The SI base unit of length, defined as the distance light travels in 1/299,792,458 of a second.
cm or centimeter or centimeters or centimetre or centimetres	Centimeters	A unit of length equal to one hundredth of a meter.
in or ″ or inch or inches	Inches	A unit of length in the imperial and US customary systems, equal to 2,54 centimeters.
ft or ′ or foot or feet	Feet	A unit of length in the imperial and US customary systems, equal to 12 inches or 0,3048 meters.
ftUS or ftUSD or footUS or feetUS	Feet (US Survey)	A unit of length used in US land surveying, slightly longer than the international foot.
mi or mile or miles	Miles	A unit of length in the imperial and US customary systems, equal to 5,280 feet or approximately 1,609,34 meters.
NM or nmi or nautical mile or nautical miles	Nautical Miles	A unit of length used in navigation, approximately equal to one minute of latitude (1,852 meters).
yd or yard or yards	Yards	A unit of length in the imperial and US customary systems, equal to 3 feet or 0,9144 meters.
mm or millimeter or millimeters or ,millimetre or millimetres	Millimeters	A unit of length equal to one thousandth of a meter.
μm or micrometer or micrometers or micrometre or micrometres	Micrometers	A unit of length equal to one millionth of a meter (also known as a micron).
nm or nanometer or nanometers or nanometre or nanometres	Nanometers	A unit of length equal to one billionth of a meter.
Å or angstrom or angstroms or ångström or ångströms	Angstroms	A non-SI unit of length equal to 10^-10 meters, often used for atomic and molecular scales.
pm or picometer or picometers or picometre or picometres	Picometers	A unit of length equal to one trillionth of a meter.
km or kilometer or kilometers or kilometre or kilometres	Kilometers	A unit of length equal to one thousand meters.
au or AU or astronomical unit or astronomical units	Astronomical Units	The average distance from the Earth to the Sun, approximately 149.6 million kilometers, used for distances within the solar system.
ly or light year or light years or light-year or light-years	Light Years	The distance light travels in one Julian year in a vacuum, approximately 9,46 trillion kilometers.
pc or parsec or parsec	Parsec	A unit of length used in astronomy, equal to about 3,26 light-years or 30,86 trillion kilometers.
mil or thou or mils	Mils	A unit of length equal to one thousandth of an inch, often used for measuring thickness.

Masses

Symbol	Name	Definition
g or gram or grams	Gram	A metric unit of mass, equal to one thousandth of a kilogram.
hg or hectogram or hectograms	Hectogram	A metric unit of mass, equal to 100 grams or one tenth of a kilogram.
kg or kilogram or kilograms	Kilogram	The SI base unit of mass, defined by a fixed numerical value of the Planck constant.
lb or pound or pounds	Pounds	A unit of mass in the imperial and US customary systems, equal to 0,45359237 kilograms.
oz or ounce or ounces	Ounces	A unit of mass in the imperial and US customary systems, equal to 1/16 of a pound.
t or ton or tons	Tons	A metric ton (tonne), equal to 1,000 kilograms or approximately 2,204,6 pounds.
mg or milligram or milligrams	Milligram	A metric unit of mass, equal to one thousandth of a gram.
u or unified atomic mass unit	Unified Atomic Mass Unit	A unit of mass used to express atomic and molecular masses, approximately 1,6605 x 10^-27 kg.
ct or carat or carats	Carats	A unit of mass used for gemstones and pearls, equal to 200 milligrams (0,2 grams).
cg or centigram or centigrams	Centigram	A metric unit of mass, equal to one hundredth of a gram.
dwt or pennyweight or pennyweights	Pennyweights	A unit of mass in the troy weight system, equal to 24 grains or approximately 1,555 grams, often used for precious metals.
oz t or troy ounce or troy ounces	Troy Ounces	A unit of mass in the troy weight system, equal to 31,1034768 grams, commonly used for precious metals.
st. or stone or stones	Stones	An imperial unit of mass, equal to 14 pounds or approximately 6,35029 kilograms, mainly used in the UK and Ireland for body weight.
fg or femtogram or femtograms	Femtogram	A metric unit of mass, equal to 10^-15 grams.
pg or picogram or picograms	Picogram	A metric unit of mass, equal to 10^-12 grams.
ng or nanogram or nanograms	Nanogram	A metric unit of mass, equal to 10^-9 grams.
µg or microgram or micrograms	Microgram	A metric unit of mass, equal to 10^-6 grams.
dg or decigram or decigrams	Decigram	A metric unit of mass, equal to one tenth of a gram.

Numeral Systems

Symbol	Name	Definition
₁₀ or decimal or base-10 or denary	Decimal	A base-10 numeral system, using digits 0 through 9.
₁₆ or hexadecimal or base-16 or hex	Hexadecimal	A base-16 numeral system, using digits 0-9 and letters A-F.
₈ or octal or base-8 or oct	Octal	A base-8 numeral system, using digits 0 through 7.
₂ or binary or base-2 or bin	Binary	A base-2 numeral system, using only two digits: 0 and 1.

Powers

Symbol	Name	Definition
W or watt or watts	Watt	The SI unit of power, defined as one joule per second.
mW or milliwatt or milliwatts	Milliwatt	A unit of power equal to one thousandth of a watt.
kW or kilowatt or kilowatts	Kilowatt	A unit of power equal to one thousand watts.
MW or megawatt or megawatts	Megawatt	A unit of power equal to one million watts.
GW or gigawatt or gigawatts	Gigawatt	A unit of power equal to one billion watts.
hp or european horse power	European Horse Power	A unit of power, commonly used in Europe, equal to approximately 735,5 watts.
imperial hp or imperial horse power	Imperial Horse Power	A unit of power, commonly used in the imperial system, equal to approximately 745,7 watts.

Pressures

Symbol	Name	Definition
Pa or pascal or pascals	Pascal	The SI derived unit of pressure, defined as one newton per square meter.
atm or atmosphere or atmospheres	Atmosphere	A non-SI unit of pressure, approximately equal to the average atmospheric pressure at sea level.
bar or bars	Bar	A metric unit of pressure, approximately equal to 100,000 pascals or close to one standard atmosphere.
mbar or millibar or millibars	Millibar	A unit of pressure equal to one thousandth of a bar, commonly used in meteorology.
psi or pounds per square inch	Psi	A unit of pressure in the imperial and US customary systems, defined as one pound-force per square inch.
torr or torricelli or millimeters of mercury	Torr	A unit of pressure defined as 1/760 of a standard atmosphere, approximately equal to one millimeter of mercury.
hPa or Hectopascal	Hectopascal	A unit of pressure equal to 100 pascals, often used in meteorology for atmospheric pressure.
inHg or inches of mercury	Inch of Mercury	A non-SI unit of pressure, defined as the pressure exerted by a column of mercury one inch high at a specific temperature.

Shoe sizes

Symbol	Name	Definition
shoe centimeter or shoe centimeters	Shoe Centimeter	A shoe size unit based on the measured length in centimeters.
shoe inch or shoe inches	Shoe Inch	A shoe size unit based on the measured length in inches.
eu or eu china	EU China	A shoe size standard commonly used in Europe and China, based on the length of the last.
uk india child	UK India (Child)	Shoe size standard for children in the United Kingdom and India.
uk india man	UK India (Man)	Shoe size standard for men in the United Kingdom and India.
uk india woman	UK India (Woman)	Shoe size standard for women in the United Kingdom and India.
us canada child	USA Canada (Child)	Shoe size standard for children in the United States and Canada.
us canada man	USA Canada (Man)	Shoe size standard for men in the United States and Canada.
us canada woman	USA Canada (Woman)	Shoe size standard for women in the United States and Canada.
jp or japan	Japan	Shoe size standard commonly used in Japan, often based on foot length in centimeters.

Speeds

Symbol	Name	Definition
m/s or meters per second	Meters per second	The SI unit of speed, representing the distance in meters traveled per second.
km/h or kilometers per hour	Kilometers per hour	A common unit of speed, representing the distance in kilometers traveled per hour.
mi/h or miles per hour	Miles per hour	A unit of speed commonly used in countries using the imperial system, representing the distance in miles traveled per hour.
kts or knots	Knots	A unit of speed commonly used in maritime and aviation, equal to one nautical mile per hour.
ft/s or feets per second	Feets per second	A unit of speed representing the distance in feet traveled per second.
min/km or minutes per kilometer	Minutes per kilometer	A unit of pace, indicating the time in minutes required to travel one kilometer.

Temperatures

Symbol	Name	Definition
°F or fahrenheit	Fahrenheit	A temperature scale where water freezes at 32°F and boils at 212°F.
°C or celsius	Celsius	A temperature scale where water freezes at 0°C and boils at 100°C; also known as centigrade.
K or kelvin	Kelvin	The SI base unit of thermodynamic temperature, with 0 K being absolute zero.
°Re or reamur	Reamur	A temperature scale where water freezes at 0°Re and boils at 80°Re.
°Rø or romer	Romer	A temperature scale where 0°Rø is the freezing point of brine and 7.5°Rø is the freezing point of pure water.
°De or delisle	Delisle	A temperature scale where 0°De is the boiling point of water and 150°De is the freezing point of water.
°R or rankine	Rankine	An absolute temperature scale related to the Fahrenheit scale, with absolute zero at 0°R (-459.67°F).

Times

Symbol	Name	Definition
s or second or seconds	Second	The SI base unit of time.
ds or decisecond or deciseconds	Decisecond	A unit of time equal to one tenth (1/10) of a second.
cs or centisecond or centiseconds	Centisecond	A unit of time equal to one hundredth (1/100) of a second.
ms or millisecond or milliseconds	Millisecond	A unit of time equal to one thousandth (1/1,000) of a second.
μs or microsecond or microseconds	Microsecond	A unit of time equal to one millionth (1/1,000,000) of a second.
ns or nanosecond or nanoseconds	Nanosecond	A unit of time equal to one billionth (1/1,000,000,000) of a second.
min or minute or minutes	Minute	A unit of time equal to 60 seconds.
h or hour or hours	Hour	A unit of time equal to 60 minutes or 3,600 seconds.
d or day or days	Day	A unit of time equal to 24 hours.
w or week or weeks	Week	A unit of time equal to 7 days.
a or y or yr or year or years	Year	A unit of time approximately equal to 365 days.
c. or century or centuries	Century	A unit of time equal to 100 years.

Volumes

Symbol	Name	Definition
m³ or cubic meter or cubic meters	Cubic Meters	The SI unit of volume, defined as the volume of a cube with sides one meter long.
L or liter or liters	Liters	A metric unit of volume, equal to 1,000 cubic centimeters or one cubic decimeter.
gal or gallon or gallons	Imperial Gallons	A unit of volume in the imperial system, equal to 4,54609 liters.
galUS or gallonUS or gallonsUS	US Gallons	A unit of volume in the US customary system, equal to 3,78541 liters.
pt or p or pint or pints	Imperial Pints	A unit of volume in the imperial system, equal to 0,568261 liters.
ptUS or pUS or pintUS or pintsUS	US Pints	A unit of volume in the US customary system, equal to 0,473176 liters.
ml or milliliter or milliliters	Milliliters	A metric unit of volume, equal to one thousandth of a liter.
tbspUS or tablespoonUS or tablespoonsUS	US Tablespoons	A unit of volume in the US customary system, equal to 14,7868 milliliters.
tbspAUS or tablespoonAUS or tablespoonsAUS	Australian Tablespoons	A unit of volume commonly used in Australia, equal to 20 milliliters.
cup or cups	Cups	A unit of volume commonly used in cooking, with varying definitions depending on the system (e.g., US Customary, Metric).
cm³ or cubic centimeter or cubic centimeters	Cubic Centimeters	A unit of volume equal to one millionth of a cubic meter.
ft³ or cubic foot or cubic feet	Cubic Feet	A unit of volume in the imperial and US customary systems, equal to the volume of a cube with sides one foot long.
in³ or cubic inch or cubic inches	Cubic Inches	A unit of volume in the imperial and US customary systems, equal to the volume of a cube with sides one inch long.
mm³ or cubic millimeter or cubic millimeters	Cubic Millimeters	A unit of volume equal to one billionth of a cubic meter.
imperial fl or fluid ounce or fluid ounces	Imperial Fluid Ounces	A unit of volume in the imperial system, equal to 28,4131 milliliters.
flUS or fluid ounceUS or fluid ouncesUS	US Fluid Ounces	A unit of volume in the US customary system, equal to 29,5735 milliliters.
gi or gill or gills	Imperial Gill	A unit of volume in the imperial system, equal to 0,142065 liters (one-quarter of an imperial pint).
liq. gi or liquid gill or liquid gills	US Gill	A unit of volume in the US customary system, equal to 0,118294 liters (one-quarter of a US pint).
liq. qt or liquid quart or liquid quarts	US Quarts	A unit of volume in the US customary system, equal to 0,946353 liters.
fl or femtoliter or femtoliters	Femtoliters	A metric unit of volume, equal to 10^-15 liters.
pl or picoliter or picoliters	Picoliters	A metric unit of volume, equal to 10^-12 liters.
nl or nanoliter or nanoliters	Nanoliters	A metric unit of volume, equal to 10^-9 liters.
µl or microliter or microliters	Microliters	A metric unit of volume, equal to 10^-6 liters.
dl or deciliter or deciliters	Deciliters	A metric unit of volume, equal to one tenth of a liter.
cl or centiliter or centiliters	Centiliters	A metric unit of volume, equal to one hundredth of a liter.