Unit Converter
Convert length, weight, temperature, volume, area, speed and time between metric and imperial units.
All Length units
| Millimetres (mm) | — |
|---|---|
| Centimetres (cm) | — |
| Metres (m) | — |
| Kilometres (km) | — |
| Inches (in) | — |
| Feet (ft) | — |
| Yards (yd) | — |
| Miles (mi) | — |
| Nautical miles (nmi) | — |
| Milligrams (mg) | — |
| Grams (g) | — |
| Kilograms (kg) | — |
| Metric tonnes (t) | — |
| Ounces (oz) | — |
| Pounds (lb) | — |
| Stone (st) | — |
| US tons (short) | — |
| Celsius (°C) | — |
| Fahrenheit (°F) | — |
| Kelvin (K) | — |
| Millilitres (ml) | — |
| Litres (l) | — |
| Cubic metres (m³) | — |
| Teaspoons (US) | — |
| Tablespoons (US) | — |
| Fluid ounces (US) | — |
| Cups (US) | — |
| Pints (US) | — |
| Quarts (US) | — |
| Gallons (US) | — |
| Gallons (imperial) | — |
| Square millimetres (mm²) | — |
| Square centimetres (cm²) | — |
| Square metres (m²) | — |
| Hectares (ha) | — |
| Square kilometres (km²) | — |
| Square inches (in²) | — |
| Square feet (ft²) | — |
| Square yards (yd²) | — |
| Acres | — |
| Square miles (mi²) | — |
| Metres per second (m/s) | — |
| Kilometres per hour (km/h) | — |
| Miles per hour (mph) | — |
| Feet per second (ft/s) | — |
| Knots (kn) | — |
| Milliseconds (ms) | — |
| Seconds (s) | — |
| Minutes (min) | — |
| Hours (h) | — |
| Days (d) | — |
| Weeks (wk) | — |
| Months (30.44 days) | — |
| Years (365.25 days) | — |
How it works
Pick a measurement type, type a value and choose the units — the result updates as you type, and the table underneath shows the same value in every other unit of that family at once. Length, weight, volume, area, speed and time all convert through a single base unit (metre, kilogram, litre, square metre, metre per second, second) using the exact international definitions: 1 inch is exactly 25.4 mm, 1 pound is exactly 0.45359237 kg, 1 US gallon is exactly 3.785411784 litres. Temperature is different because its scales have an offset as well as a slope, so Celsius, Fahrenheit and Kelvin are converted with °C = (°F − 32) × 5/9 and K = °C + 273.15; values below absolute zero are rejected. Results are rounded to six decimals and switch to scientific notation at the extremes. All of it is plain JavaScript arithmetic in your browser — no server, no upload, and it keeps working offline once the page has loaded.
Frequently asked questions
How many feet are in a meter?
One metre is 3.28084 feet, because a foot is defined as exactly 0.3048 metres. Enter 1 with metres selected and the converter shows feet along with inches (39.370079), yards, miles and every other length unit at the same time.
How do I convert Celsius to Fahrenheit?
Multiply by 9/5 and add 32: °F = °C × 9/5 + 32. So 100 °C = 212 °F and 0 °C = 32 °F. Choose Temperature in the converter and it handles Celsius, Fahrenheit and Kelvin for you, and refuses anything below absolute zero (-273.15 °C).
Does this unit converter work offline?
Yes. Every conversion factor is built into the page and all the arithmetic runs in your browser, so once the page has loaded there are no network requests. Nothing you type is sent anywhere and the tool keeps working with no connection.