Convert everyday units instantly
This converter handles the measurements people look up most: length (meters, feet, miles, inches and more), weight (kilograms, pounds, ounces, stone), temperature (Celsius, Fahrenheit, Kelvin) and volume (liters, gallons, cups, fluid ounces). Pick a category, enter a value, and choose the units — the result updates instantly.
The conversions people look up most
| From | To | Multiply by |
|---|---|---|
| Inches | Centimeters | 2.54 |
| Centimeters | Inches | 0.3937 (÷ 2.54) |
| Miles | Kilometers | 1.609 |
| Kilometers | Miles | 0.6214 |
| Kilograms | Pounds | 2.2046 |
| Pounds | Kilograms | 0.4536 |
| Liters | US gallons | 0.2642 |
| US gallons | Liters | 3.785 |
Temperature is different — it uses offsets
Length and weight convert by a simple multiplier, but temperature scales don’t start at the same zero, so they need offset formulas: °F = °C × 9/5 + 32 and °C = (°F − 32) × 5/9. Worth memorizing: 0°C = 32°F (freezing), 37°C = 98.6°F (body temperature), and 100°C = 212°F (boiling). A fast mental estimate for °C to °F: double it and add 30 — 20°C ≈ 70°F (exact is 68).
Metric and imperial, briefly
Most of the world uses the metric system (meters, kilograms, liters, Celsius); the United States mainly uses imperial/US customary units (feet, pounds, gallons, Fahrenheit). A subtlety worth knowing: a US gallon (3.785 L) is smaller than an imperial gallon (4.546 L), and US and imperial fluid ounces differ slightly too — so recipe and fuel conversions between the US and UK aren’t interchangeable. This tool uses US customary units for volume.
Everyday uses
Reading a recipe from another country, checking your height and weight in the other system, planning a road trip in the “wrong” units, or following a workout plan — a quick unit conversion clears it up. For body measurements specifically, the BMI calculator accepts both metric and imperial directly.
Frequently asked questions
How do I convert cm to inches?
Divide centimeters by 2.54. For example, 10 cm / 2.54 = 3.94 inches. Select Length, enter your value, and choose Centimeters to Inches.
How do I convert kg to pounds?
Multiply kilograms by 2.2046. For example, 70 kg x 2.2046 = 154.3 lb. Choose Weight and set Kilograms to Pounds.
How do I convert Celsius to Fahrenheit?
Multiply by 9/5 and add 32: F = C x 9/5 + 32. So 20C = 68F. A quick estimate is to double the Celsius value and add 30.
How many kilometers is a mile?
1 mile = 1.609 kilometers, and 1 kilometer = 0.6214 miles. To go from miles to km, multiply by 1.609.
Is a US gallon the same as a UK gallon?
No. A US gallon is 3.785 liters; an imperial (UK) gallon is 4.546 liters — about 20% larger. US and imperial fluid ounces differ slightly too, so US and UK volume measures aren't interchangeable.
Why does temperature need a special formula?
Because the scales don't share a zero point, temperature uses an offset (F = C x 9/5 + 32) rather than a simple multiplier like length or weight.