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Temperature Length Area Volume and Mass

Convert numeric measures across metric, customary, temperature and selected conventional reference scales.

  • Formula & worked example
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Calculator inputs

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How to use this calculator

  1. Enter the known values in the units shown. Results update as you type.
  2. Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
  3. Use the worked example to check the method. Reset restores the starting fields.

Private by default

Inputs and results stay in this browser tab. Bookify does not upload or store the values you enter.

Formula and method

In initial displayed units, Celsius 0 gives Farhenheit 32, Kelvin 273.15.

All fields in each mode represent the same reference quantity; Celsius = kelvin−273.15; Fahrenheit = 1.8×kelvin−459.67.

Worked example

Enter these known values and leave the other values blank.

Celsius
0 °C
Farhenheit
32 °F
Kelvin
273.15 K
Other temperature units
491.7 °R
Other temperature units
150 °De

Assumptions and limitations

  • Absolute temperatures must be nonnegative. The atomic-mass unit and electron, proton and neutron mass scales use CODATA 2022 central values with measured uncertainty. Solar mass, solar radius and a 7140 m² reference soccer field are conventional approximate scales, not exact physical-body or sporting-field measurements. Fluid ounces and pints default to US definitions; choose imperial definitions explicitly when needed.
  • Use compatible measurement units. Clear an unknown before solving for it, and lock independent known values when comparing changes. Currency choices label amounts without exchange-rate conversion.

Common questions

Can I solve backward from the result?

Clear the unknown and enter independent known values. A rounded whole count cannot uniquely recover a continuous dimension; keep the original measured dimensions for procurement planning.

References

Enforce absolute-temperature bounds and use explicit US fluid-volume defaults while retaining imperial unit choices. Use CODATA 2022 central values for the atomic-mass unit and electron, proton and neutron masses, with measured uncertainty. The light-year uses exactly 299792458 m/s times a 31557600-second Julian year, replacing the rounded reference factor. The parsec uses the IAU definition 648000/π astronomical units, with one astronomical unit exactly 149597870700 meters, instead of a rounded decimal factor. The international acre is exactly 43560 square international feet; Bookify replaces the rounded captured area factor. The cubic international mile uses the cube of the exact 1609.344-meter mile, replacing a rounded reciprocal factor. The US fluid ounce uses one 128th of the exact US liquid gallon, replacing the rounded captured reciprocal factor. Bookify replaces the captured rounded US gallon with the exact 3.785411784-liter definition. The US customary cup uses one sixteenth of the exact US liquid gallon, replacing the rounded captured cup volume.

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