Conversions
Unit converter
Convert length, weight, temperature, or volume. Length, weight, and volume use exact international factors. Temperature uses the standard Celsius, Fahrenheit, and Kelvin relationships.
What this means
- 100 Celsius = 212 Fahrenheit
- Length uses the exact inch of 0.0254 meters. Weight uses the exact pound of 0.45359237 kilograms. US gallons use 3.785411784 liters.
- 100 degrees Celsius is 212 degrees Fahrenheit, and 0 degrees Celsius is 32 degrees Fahrenheit.
What if
About this calculator
What this calculator does
It converts a value between two units in the same family: length, weight, temperature, or volume. Changing the family updates the unit lists.
How it is calculated
Linear units convert through a base unit. Length uses the meter, weight uses the kilogram, and volume uses the liter:
result = value * (from factor) / (to factor)
Exact factors include 1 inch = 0.0254 m, 1 foot = 0.3048 m, 1 mile = 1609.344 m, 1 pound = 0.45359237 kg, and 1 US gallon = 3.785411784 L. Quarts, pints, cups, and fluid ounces are exact fractions of that gallon.
Temperature converts through Celsius:
F = C * 9/5 + 32, and K = C + 273.15
How to read the result
The sentence shows both units. The numeric result is the converted value rounded to 6 decimal places for the secondary line. The sentence keeps up to 8 decimal places and drops trailing zeros.
Which gallon?
Volume uses US liquid gallons, quarts, pints, cups, and fluid ounces. Imperial gallons are a different size and are not in this list.
Sources and method
Exact conversion factors from NIST where they are defined. Unit tests check round trips and known values.
Questions
Is 100 Celsius exactly 212 Fahrenheit?
Yes. The formula is Celsius times 9/5, plus 32. 100 times 9/5 is 180, and 180 plus 32 is 212.
Why is an inch 0.0254 meters?
That is the exact international inch. The calculator does not use a rounded 2.54 centimeters beyond that definition.
Which pound is used?
The international avoirdupois pound, exactly 0.45359237 kilograms. An ounce is one sixteenth of that pound.
Can temperature be negative?
Yes. Length, weight, and volume reject negative inputs because a negative length is not meaningful here.
Are UK gallons included?
No. The gallon in this list is the US liquid gallon of 3.785411784 liters.