FreeNo signup
Unit converters
These converters cover the units people actually need: length, mass, time, temperature and drawing scale. Each one shows the result in every unit at once, not just the single target you picked.
The factors are exact. Imperial units are defined against metric ones by international agreement, so an inch is exactly 2.54 cm and a pound is 0.45359237 kg.
Calculators in this section
- Time Unit Convertertime converterOpen →
- Temperature Convertertemperature converterOpen →
- Length Converterlength converterOpen →
- Weight Converterweight converterOpen →
- Scale Calculatorscale calculatorOpen →
- Data Storage Converterdata storage converterOpen →
- Area Converterarea converterOpen →
- Power Converterpower converterOpen →
- Speed Converterspeed converterOpen →
- Pressure Converterpressure converterOpen →
- Volume Convertervolume converterOpen →
What to keep in mind when converting
- Metric prefixes are powers of ten: kilo is a thousand, centi is a hundredth, milli is a thousandth.
- Imperial units have exact metric definitions, so there is no need to round the factors.
- Temperature is not a simple multiplication: the scales have different zero points.
- Months and years use average lengths, otherwise the result would depend on a specific calendar year.
Frequent conversions
| Question | Answer |
|---|---|
| Centimetres in a metre | 100 cm |
| Centimetres in an inch | 2.54 cm |
| Kilograms in a pound | 0.4536 kg |
| Hours in a day | 24 hours |
| 100 °C in Fahrenheit | 212 °F |
Frequently asked questions
How is a converter different from a calculator?
A converter expresses the same quantity in different units, while a calculator derives a new quantity from a formula.
Why does my result differ from a table I found elsewhere?
Usually because that table rounded the factor. These converters use exact values and round only the displayed result.
Can I enter decimal values?
Yes — use either a dot or a comma as the decimal separator.