How to use it
- Choose a category: length, weight, temperature, area or volume.
- Enter the value and select the unit you are converting from and to.
- Read the main result, or scan the table below for all other units.
How it works
Every length, weight, area and volume unit is stored as one exact factor against a base unit (meter, kilogram, square meter, liter). Your value is multiplied into the base unit and divided back out, so you never stack two rounded factors. Temperature is the exception: Celsius, Fahrenheit and Kelvin start from different zeros, so the converter shifts as well as scales.
Worked example
72 °F to Celsius: (72 − 32) × 5/9 = 22.2 °C. Five pounds to kilograms: 5 × 0.45359237 = 2.268 kg. That factor is exact by definition, which is why the converter can show more decimals than you will ever need.
Assumptions and limits
- A US gallon is 3.785 L and an imperial (UK) gallon is 4.546 L, so both are listed separately. Quarts, cups and fluid ounces here are US measures.
- Results are rounded for display only. The calculation keeps full precision.
- Cups and spoons of flour or sugar depend on density, so they live in the cooking converter, not here.
Frequently asked questions
How many centimeters are in an inch?
Exactly 2.54 cm. The inch has been defined this way by international agreement since 1959.
Why is temperature different from other conversions?
Celsius and Fahrenheit have different zero points, so the converter applies an offset as well as a scale: °F = °C × 9/5 + 32.
Are US and UK gallons the same?
No. A US gallon is about 3.785 liters while an imperial (UK) gallon is about 4.546 liters. Both are listed separately.