Unit Converter
Convert between hundreds of units instantly. Switch categories with one click — length, weight, temperature, volume, speed, area, and data.
1 m = 0.001 km
- m
- 1
- km
- 0.001
- cm
- 100
- mm
- 1000
- nm
- 1000000000
- mi
- 0.0006213711922
Common conversions
How to use Unit Converter
The unit converter handles length, weight, temperature, area, volume, speed, time, data and energy conversions — all within a single interface. Enter a value and source unit; the result appears in all compatible units simultaneously. Supports both metric and imperial systems with full precision and scientific notation for very large or small values.
- Select a unit category (e.g. Length, Temperature).
- Enter a numeric value in the source unit input.
- Select the source unit from the dropdown.
- All target unit values update instantly — copy any result with one click.
Your data never leaves your device — 100% private processing.
Metric vs imperial and everyday conversions
The metric system uses decimal multiples (kilo = 1,000, milli = 0.001) making conversions between metric units trivial. The imperial system (miles, feet, pounds, Fahrenheit) uses arbitrary conversion factors that must be memorised. Common cross-system conversions: 1 inch = 2.54 cm, 1 mile = 1.609 km, 1 kg = 2.205 lbs, 1 litre = 0.264 US gallons. Temperature conversion requires an offset: °C = (°F − 32) × 5/9.
| Metric | Imperial | Factor |
|---|---|---|
| 1 km | 0.621 miles | × 0.621371 |
| 1 kg | 2.205 lbs | × 2.20462 |
| 1 litre | 0.264 US gal | × 0.264172 |
| 1 m² | 10.764 ft² | × 10.7639 |
| 0°C | 32°F | × 9/5 + 32 |
Data size units explained
Data size has two parallel standards. The SI decimal standard: 1 kilobyte (KB) = 1,000 bytes, 1 megabyte (MB) = 1,000,000 bytes. The IEC binary standard: 1 kibibyte (KiB) = 1,024 bytes, 1 mebibyte (MiB) = 1,048,576 bytes. Hard drive manufacturers use decimal, while RAM and operating systems traditionally use binary. This tool uses binary (1 KB = 1,024 bytes) for data conversions by default.
Glossary
- SI unit
- International System of Units — the modern metric system.
- Imperial unit
- Traditional units used mainly in the United States (inches, pounds, Fahrenheit).
- Conversion factor
- The ratio used to convert one unit to another.
- Derived unit
- A unit formed from base SI units by multiplication or division, e.g. m/s for speed.
Related reading
Frequently Asked Questions
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Why use Unit Converter?
- Real-time unit conversion with live preview
- Covers hundreds of unit types in one place
- High-precision results with up to 10 decimal places
- No need to memorise formulas — just type and convert
Common use cases
- Convert recipe measurements from cups to grams
- Calculate fuel economy in miles per gallon vs litres per 100km
- Convert temperatures for international travel
- Convert dimensions between metric and imperial for DIY projects
- Calculate distance conversions for running or cycling plans
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