How to Convert Units Online
Whether you're a student working on a physics assignment, a cook converting a recipe from cups to milliliters, a traveler switching between miles and kilometers, or an engineer converting between metric and imperial measurements — our free Unit Converter makes it instant.
- Select a category: Choose from Length, Weight, Temperature, Speed, Volume, Area, or Time.
- Pick your units: Select the "From" unit and the "To" unit from the dropdown menus.
- Enter a value: Type the number you want to convert. The result updates in real-time as you type.
Supported Unit Categories
- Length: Millimeters, Centimeters, Meters, Kilometers, Inches, Feet, Yards, Miles
- Weight: Milligrams, Grams, Kilograms, Ounces, Pounds
- Temperature: Celsius, Fahrenheit, Kelvin (uses proper formulas, not simple ratios)
- Speed: m/s, km/h, mph, Knots
- Volume: Milliliters, Liters, US Gallons, US Cups, Tablespoons, Teaspoons
- Area: mm², cm², m², km², in², ft², Acres, Hectares
- Time: Seconds, Minutes, Hours, Days, Weeks
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Frequently Asked Questions
What units can I convert?
Our converter supports 7 categories with 40+ units: Length, Weight, Temperature, Speed, Volume, Area, and Time — covering the most commonly needed conversions.
How accurate is this converter?
We use precise scientific conversion factors. Temperature conversions use correct formulas (°C to °F = C × 9/5 + 32), not approximations. Results show up to 6 significant digits.
Does it work offline?
Yes! Once the page loads, the converter works entirely in your browser without an internet connection. Bookmark it for quick access.