| Millimeter (mm) | 1 |
| Centimeter (cm) | 0.1 |
| Meter (m) | 0.001 |
| Kilometer (km) | 0.000001 |
| Inch (in) | 0.03937 |
| Foot (ft) | 0.003281 |
| Yard (yd) | 0.001094 |
| Mile (mi) | 6.2137e-7 |
About Unit Converter — Length, Weight & Temperature
This free unit converter turns a value from one unit into another across the measurements you reach for every day — length, mass, temperature, area, volume, speed, and time. Switch between metric and imperial (meters and miles, kilograms and pounds, Celsius and Fahrenheit) without hunting for a formula or trusting a calculator you can't see.
Pick a category, type a value, and choose the units to convert between. A live table shows the same value in every unit of that category at once, so you can compare at a glance. Temperature is handled correctly with proper offset formulas — not a naive ratio — so 0 °C maps to exactly 32 °F and 273.15 K.
Everything runs locally in your browser. Nothing you type is uploaded, so the converter keeps working with the network unplugged.
Features
- Length, mass, temperature, area, volume, speed, and time in one place
- Metric and imperial both directions — km↔mi, kg↔lb, °C↔°F
- Accurate temperature conversion using offset formulas, not ratios
- Live table showing your value in every unit of the category
- Fully offline — your input never leaves the device
How to use
- Choose a category — Length, Mass, Temperature, and so on.
- Enter the value you want to convert.
- Pick the "from" and "to" units (use swap to reverse them).
- Read the result, or scan the live table for every unit at once.
Frequently asked questions
How do I convert Celsius to Fahrenheit?
Multiply the Celsius value by 9/5 and add 32: °F = °C × 9/5 + 32. So 20 °C is 68 °F and 100 °C is 212 °F. Pick the Temperature category, type the value, and the converter applies this formula for you in both directions.
Why convert temperature differently from other units?
Temperature scales have an offset, not just a scale factor. 0 °C is not "zero degrees" of heat — it equals 32 °F and 273.15 K. The converter applies the proper formulas (°F = °C × 9/5 + 32, K = °C + 273.15) instead of multiplying by a single ratio.
How many meters are in a mile?
One international mile is exactly 1609.344 meters. The converter uses these exact internationally-defined factors, so round-trips (m → mi → m) return the original value.
Are US or imperial gallons used for volume?
The volume units here use US customary measures — a US gallon is about 3.785 liters, and cups, pints, and quarts follow the US definitions. Metric volume (milliliters, liters) is exact.
Is my data sent to a server?
No. All conversions happen in your browser with plain arithmetic. Nothing is uploaded, logged, or tracked, and the tool works completely offline.
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Everything runs locally in your browser — your input is never uploaded.