About the Unit Converter
Unit Master's main converter handles the six measurement families most people need every day: length, weight, temperature, volume, area, and speed. Every conversion is calculated in your browser, so the result appears as fast as you can type. Use it for school assignments, travel, DIY projects, recipes, fitness tracking, or quickly translating between metric and imperial units when you're working with international documents.
How to use it
- Pick a measurement category from the picker (length, weight, temperature, volume, area, or speed).
- Choose the unit you're converting from and the unit you're converting to.
- Type a value into either field — the other side updates instantly.
- Use the swap button to flip the units, or copy the result with the copy button next to the output.
Common conversions
| 1 inch | 2.54 cm |
| 1 foot | 30.48 cm |
| 1 yard | 0.9144 m |
| 1 mile | 1.609 km |
| 1 pound | 0.4536 kg |
| 1 ounce | 28.35 g |
| 1 US gallon | 3.785 L |
| 1 UK gallon | 4.546 L |
| 100°F | 37.78°C |
| 0°C | 32°F |
Frequently asked questions
- Is Unit Master accurate enough for engineering or scientific work?
- Yes. Calculations use double-precision floating-point math and the conversion factors come from the International System of Units (SI) definitions. For most engineering and scientific work the precision is more than sufficient — the limiting factor is usually the precision of your input value, not the converter.
- Why are there two different gallons?
- The United States kept the old English wine gallon (231 in³ ≈ 3.785 L) after independence. The United Kingdom redefined its gallon as 277.42 in³ ≈ 4.546 L in 1824. A US gallon and a UK gallon are not the same volume — Unit Master treats them as separate units so you don't mix them up.
- Does it work offline?
- Yes. Unit Master is a Progressive Web App. After your first visit it caches the assets locally, so unit, cooking, calculator and Roman-numeral conversions all work without an internet connection. Only the currency converter needs the network to refresh live exchange rates.
- Do you store the values I enter?
- No. All conversions run client-side and nothing you type leaves your device unless you explicitly save a conversion to your Unit Master account. The site uses local storage only to remember your last-used units and theme.
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