Unit Converter (Metric system, US customary units, etc.) / Tool
How to use this tool
This is a unit converter that runs in your browser. Interconvert metric, United States customary units / Imperial units, and other systems of units with other systems of units.
 Entering a value in any unit will automatically convert it to another unit.
 Rounded to the fourteenth decimal place.
 A number with many digits may appear as
1e9
. This is the computer’s exponential representation, where “e” is a power of 10.
e.g. 1e3 = 10^{3} = 1,000
e.g. 1e3 = 10^{3} = 0.001  This tool does not check the lower limit, so even if it is less than 0 Kelvin, it will be converted without error. Please note.
Metric unit conversion
The metric system is a system of units based on the meter as a unit of length and the kilogram as a unit of mass.
Units  Symbols  Conversion 

Nanometre  nm  10^{9} m 
Micrometre  μm  10^{6} m 
Millimetre  mm  10^{3} m 
Centimetre  cm  10^{2} m 
Decimetre  dm  10^{1} m 
Decametre  dam  10^{1} m 
Hectometre  hm  10^{2} m 
Kilometre  km  10^{3} m 
Megametre  Mm  10^{6} m 
Units  Symbols  Conversion 

Nanogram  ng  10^{9} g 
Microgram  μg  10^{6} g 
Milligram  mg  10^{3} g 
Centigram  cg  10^{2} g 
Decigram  dg  10^{1} g 
Decagram  dag  10^{1} g 
Hectogram  hg  10^{2} g 
Kilogram  kg  10^{3} g 
Megagram tonne 
Mg t 
10^{6} g 
NonSI unit of length: Nautical mile conversion
Historically, it was defined as the meridian arc length corresponding to one minute (1/60 of a degree) of latitude. Today the international nautical mile is defined as exactly 1,852 metres (6,076 ft; 1.151 mi).
$1nm = 1852m$
NonSI units of area: Hectare / Are conversion
One hectare is 10,000 square meters and one hectare is 100 square meters, but neither is an SI unit.
Units  Symbols  Conversion 

Are Square decametre 
a dam^{2} 
10^{2} m^{2} 
Hectare Square hectometre 
ha hm^{2} 
10^{4} m^{2} 
Square kilometre  km^{2}  10^{6} m^{2} 
NonSI units of volume: Liter conversion
One liter is defined as the volume of a cube of 10 cm on each side (= 1dm^{3}).
Units  Symbols  Conversion  Metric conversion 

Microliter  µL  10^{−6} L  1 mm^{3} 
Milliliter  mL  10^{−3} L  1 cm^{3} 
Centiliter  cL  10^{−2} L  10^{1} cm^{3} 
Deciliter  dL  10^{−1} L  10^{2} cm^{3} 
Liter  L  10^{0} L  10^{3} cm^{3} (1 dm^{3}) 
Decaliter  daL  10^{1} L  10^{4} cm^{4} (10^{1} dm^{3}) 
Hectoliter  hL  10^{2} L  10^{5} cm^{5} (1^{2} dm^{3}) 
Kiloliter  kL  10^{3} L  1 m^{3} 
Megaliter  ML  10^{6} L  10^{3} m^{3} 
United States customary units / Imperial units conversion
The United States customary units / Imperial units is a system of units used mainly in the United States, with the yard as the basic unit of length and the pound as the basic unit of mass.
Units  Symbols  Conversion  Metric conversion 

Inch  in  25.4 mm  
Foot  ft  12 in  30.48 cm 
Yard  yd  3 ft  0.9144 m 
Chain  ch  22 yd  20.1168 m 
Furlong  fur  220 yd  201.168 m 
Mile  mi  1760 yd  1609.344 m 
Units  Symbols  Conversion  Metric conversion 

Grain  gr  0.06479891 g  
Dram  dr  27 × 11/32 gr  1.7718451953125 g 
Ounce  oz  16 dr  28.349523125 g 
Pound  lb  16 oz  0.45359237 kg 
Hundredweight (US)  cwtUS  100 lb  45.359237 kg 
Ton (US)  s.t.  2000 lb  907.18474 kg 
Stone (UK)  st  14 lb  6.35029318 kg 
Quarter (UK)  qtr  28 lb  12.70058636 kg 
Hundredweight (UK)  cwtUK  112 lb  50.80234544 kg 
Ton (UK)  l.t.  2240 lb  1016.0469088 kg 
In addition, different units are used in the U.S. and the U.K. for volume.
Volume of liquids (US) conversion
Units  Symbols  Definitions  Liter 

Fluid dram (US)  fl.dr.  1/8 fl.oz.  3.6966911953125 mL 
Fluid ounce (US)  fl.oz.  1/16 pt  29.5735295625 mL 
Pint (US)  pt  1/2 qt  473.176473 mL 
Quart (US)  qt  1/4 gal  0.946352946 L 
Gallon (US)  gal  231 cu.in.  3.785411784 L 
Oil barrel  bbl  158.987294928 L 
※バレルは石油以外では定義が異なります。
Volume of liquids (UK) conversion
Units  Symbols  Definitions  Liter 

Fluid dram (UK)  fl.dr.  1/8 fl.oz.  3.5516328125 mL 
Fluid ounce (UK)  fl.oz.  1/5 gal  28.4130625 mL 
Pint (UK)  pt  1/2 qt  568.26125 mL 
Quart (UK)  qt  1/4 gal  1.1365225 L 
Gallon (UK)  gal  4.54609 L 
Japanese units of measurement (shaku–kan system) conversion
The shaku–kan system is a traditional Japanese units of measurement , with the basic unit being the shaku for length and the kan for mass.
 Length: The basic unit is the “shaku (尺)“. 1 shaku is defined as 10/33 of a meter.
 Mass: The basic unit is the “kan (貫)“. 1 kan is defined as 3.75 kg.
 Area: The basic unit is the “tsubo (坪)“. 1 tsubo is defined as 400/121 of a m^{2}.
 Volume: The basic unit is the “shō (升)“. 1 shō is defined as 2401/1331000 of a m^{3}.
Units  Conversion  Metric conversion 

寸 sun 
0.1尺  1/33 m (≈30.3030 mm) 
尺 shaku 
10/33 m (≈30.3030 cm) 

丈 jō 
10尺  100/33 m (≈3.03030 m) 
間 ken 
6尺  60/33 m (≈1.81818 m) 
町 chō 
60間  1200/11 m (≈109.09 m) 
里 ri 
36町  43200/11 m (≈3927.273 m) 
Units  Conversion  Metric conversion 

匁 momme 
3.75 g  
両 ryō 
10匁  37.5 g 
斤 kin 
16両  600 g 
貫 kan 
100両  3.75 kg 
Units  Conversion  Metric conversion 

勺 shaku 
1/10合  4/121 m^{2} (≈330.58 cm^{2}) 
合 gō 
1/10坪  40/121 m^{2} (≈0.33058 m^{2}) 
坪/歩 tsubo 
400/121 m^{2} (≈3.3058 m^{2}) 

畝 se 
30坪  12000/121 m^{2} (≈99.174 m^{2}) 
反 tan 
10畝  120000/121 m^{2} (≈991.736 m^{2}) 
町 chō 
10反  1200000/121 m^{2} (≈9917.355 m^{2}) 
畳/帖 jō 
1.62 m^{2} 
Units  Conversion  Metric conversion 

勺 shaku 
1/10合  ≈18.039 mL 
合 gō 
1/10升  ≈180.391 mL 
升 shō 
≈1.804 L (2401/1331000 m^{3}) 

斗 to 
10升  ≈18.039 L 
石 koku 
10斗  ≈180.391 L 
Unit of force conversion
The unit of force in the International System of Units (SI) is the newton.
Units  Symbols  Definitions 

Newton  N  The force which gives a mass of 1 kg an acceleration of 1 m/s^{2}. 
Dyne  dyn  The force which gives a mass of 1 g an acceleration of 1 cm/s^{2}. 
Kilogramforce  kgf  The magnitude of the force exerted on a mass of 1 kg under normal gravity. 
Poundforce  lbf  Equal to the gravitational force exerted on a mass of 1 lb on the surface of Earth. 
Poundal  pdl  Defined as the force necessary to accelerate 1 poundmass at 1 ft/s^{2}. 
The conversion formula is as follows
$1 N = 1 kg·m/s^2$
$1 dyn = 10^{−5} N$
$1 kgf = 9.80665 N$
$1 lbf = 4.4482216152605 N$
$1 pdl = 0.138254954376 N$
Unit of pressure conversion
The unit of force in the International System of Units (SI) is the pascal.
Units  Symbols  Definitions 

Pascal  Pa  1 Pa is the pressure exerted by a force of magnitude 1 N perpendicularly upon an area of 1 m^{2}. 
Bar  bar  Equal to 100 kPa. 
Standard atmosphere  atm  International standard for atmospheric pressure. 
Technical atmosphere  at  Equal to 1 kgf/cm^{2}. 
Torr  Torr  1/760 of standard atmosphere. 
Millimetre of mercury  mmHg  Same as tor. 
Meter of water  mH2O  Water pressure at 1 m depth. 
Inch of water  inH2O  Water pressure at 1 in depth 
Pound per square inch  psi  Pressure or stress exerting a force of 1 N per 1 sq.in. 
The conversion formula is as follows
$1 bar = 10^5 Pa = 100 kPa$
$1 atm = 101325 Pa$
$1 at = 98066.5 Pa$
$1 Torr = 1 mmHg = {\dfrac {1}{760}} atm = {\dfrac {101325}{760}} Pa \approx 133.322 Pa$
$1 mH_2O = 10^2 cmH_2O = 10^3 mmH_2O = 9806.65 Pa$
$1 inH_2O = {\dfrac {1}{12}} ftH_2O = 249.0899 Pa$
$1 psi = 6894.76 Pa$
Unit of energy conversion
The unit of force in the International System of Units (SI) is the joule.
Units  Symbols  Definitions 

Joule  J  Work done when a force of 1 N moves an object 1 m. 
Erg  erg  Work done when a force of 1 dyn moves an object 1 cm. 
Kilogramforce  kgf·m  Work done when a force of 1 kgf moves an object 1 m. 
Footpoundal  ft·pdl  Work done when a force of 1 pdl moves an object 1 ft. 
Footpound  ft·lbf  Work done when a force of 1 lbf moves an object 1 ft. 
Kilowatthour  kW·h  1000 times more work at a power rate of 1 W per hour. (3600 times that of J) 
Calorie  cal  Heat to raise the temperature of 1 g of water by 1 °C. 
British thermal unit  Btu  Heat to raise the temperature of 1 lb of water by 1 °C. 
Electronvolt  Btu  Kinetic energy gained by an electron by passing a potential difference of 1 V in vacuum. 
TNT equivalent  t  Explosive power of 1 ton of TNT. 
The conversion formula is as follows
$1 erg = 10^{7} J$
$1 cal_{th} = 4.184 J$
$1 cal_{IT} = 4.1868 J$
$1 kgf·m = 9.80665 J$
$1 ft·pdl = 0.0421401100938048 J$
$1 ft·lbf = 1.3558179483314004 J$
$1 kW·h = 3.6 \times 10^6 J = 3.6 MJ$
$1 Btu = 1055.05585262 J$
$1 eV = 1.602176634 \times 10^{−19} J$
$1 t = 4.184 \times 10^9 J$
Unit of temperature conversion
The unit of force in the International System of Units (SI) is the kelvin.
Units  Symbols  Definitions 

Kelvin  K  1/100 of the temperature difference between the boiling and freezing points of water. 
Celsius  °C  Kelvin  273.15 
Fahrenheit  °F  The freezing point of fresh water is 32 degrees, the boiling point is 212 degrees, and the interval between them is divided into 180 equal parts to make 1 degree. 
Rankine  °R  A unit of temperature in the same temperature interval as Fahrenheit, with absolute zero being 0. 
Delisle  °De  Unit of boiling point of water is 0 degrees and freezing point is 150 degrees. 
Newton  °N  Unit where the temperature when snow melts is 0 degrees and the temperature when water boils is 33 degrees. 
Réaumur  °Ré  A unit of temperature that is rarely used today. 
Rømer  °Rø  A unit of temperature that is rarely used today. 
The conversion formula is as follows
$0 K = \text{Absolute zero}$
$[°C] = [K]  273.15$
$[°F] = [K] \times {\dfrac {9}{5}}  459.67$
$[°F] = [°C] \times {\dfrac {9}{5}} + 32$
$[°R] = [°K] \times {\dfrac {9}{5}}$
$[°De] = (100  [°C]) \times {\dfrac {3}{2}}$
$[°N] = [°C] \times {\dfrac {33}{100}}$
$\text{[°Ré]} = [°C] \times {\dfrac {4}{5}}$
$\text{[°Rø]} = [°C] \times {\dfrac {21}{40}} + 7.5$
Unit of time conversion
The unit of force in the International System of Units (SI) is the seconds.
Units  Converted value  Units  Converted value 

1 year  365 days  1 day  24 hours 
1 month  30 days  1 hour  60 minutes 
1 week  7 days  1 minutes  60 seconds 
Unit of tatami mats conversion
Jō (帖, 畳) is a unit of measurement used to express the floor area of a room.
Jō (帖)
“畳” varies in size, but “帖” is clearly defined as 1.62 square meters.
Jō (畳)
There are multiple types of “畳” dimensions, and the area varies depending on which dimension “畳” is based on. There seem to be two reasons for the creation of multiple types.
 The standard 1間 (ken) dimension varies from period to period and region to region.
 Whether tatami split (based on tatami) or pillar split (based on pillar) varies by period and region.
Name  Split  1間  Size  Area 

Kyōma  Tatami split  6尺3寸  3尺1寸5分×6尺3寸  ≈1.82405 m^{2} 
Chūkyōma  Tatami split  6尺  3尺×6尺  ≈1.6562 m^{2} 
Edoma  Pillar split  6尺  ≈2尺9寸×5尺8寸  ≈1.5488 m^{2} 
Danchima    5尺6寸  2尺8寸×5尺6寸  ≈1.445 m^{2} 
62 ma    6尺2寸  3尺1寸×6尺2寸  ≈1.7672 m^{2} 
61 ma    6尺1寸  3尺5分×6尺1寸  ≈1.71125 m^{2} 
Unit of bit/byte conversion
$1byte = 8bit$
$1KB = 1024byte$
$1MB = 1024KB = 1024^2byte$
1 KB is 1024 Bytes? or 1000 Bytes?
This tool converts 1 kilobyte (KB) to 1024 bytes.
But originally kilo is $10^3$. These are called metric prefixes.
Metric prefix  Name  Base 10 

K  kilo  $10^3$ = 1,000 
M  mega  $10^6$ = 1,000,000 
G  giga  $10^9$ = 1,000,000,000 
T  tera  $10^{12}$ = 1,000,000,000,000 
P  peta  $10^{15}$ = 1,000,000,000,000,000 
E  exa  $10^{18}$ = 1,000,000,000,000,000,000 
Z  zetta  $10^{21}$ = 1,000,000,000,000,000,000,000 
Y  yotta  $10^{24}$ = 1,000,000,000,000,000,000,000,000 
But since computers are binary numbers, $10^n$ is inconvenient.
$1bit = 2^1 = 2$
$2bit = 2^2 = 4$
$3bit = 2^3 = 8$
…
$8bit = 2^8 = 256$
$9bit = 2^9 = 512$
$10bit = 2^{10} = 1024$
Therefore, the computer decided as follows.
 KB: 1,024byte
 MB: 1,024KB
 GB: 1,024MB
But this conversion method is often confusing. It is recommended to use a binary prefix to ensure a distinction.
Binary prefix  Name  Base 10 

Ki  kibi  $2^{10}$ = 1,024 
Mi  mebi  $2^{20}$ = 1,048,576 
Gi  gibi  $2^{30}$ = 1,073,741,824 
Ti  tebi  $2^{40}$ = 1,099,511,627,776 
Pi  pebi  $2^{50}$ = 1,125,899,906,842,624 
Ei  exbi  $2^{60}$ = 1,152,921,504,606,846,976 
Zi  zebi  $2^{70}$ = 1,180,591,620,717,411,303,424 
Yi  yobi  $2^{80}$ = 1,208,925,819,614,629,174,706,176 