Unit Converter
Instantly convert between units of length, weight, temperature, area, volume, speed, time, and data — all in your browser
Quick Conversions
Real-Time Conversion
See results instantly as you type. No need to press a convert button — everything updates in real time.
100% Accurate
Uses precise conversion factors and proper formulas for temperature. No approximations or rounding errors.
Works Everywhere
Fully responsive design works perfectly on phones, tablets, and desktops. All conversions run in your browser.
Supported Conversion Categories
📏 Length
Millimeter, Centimeter, Meter, Kilometer, Inch, Foot, Yard, Mile, Nautical Mile
⚖️ Weight
Milligram, Gram, Kilogram, Metric Ton, Ounce, Pound, Stone, US Ton
🌡️ Temperature
Celsius, Fahrenheit, Kelvin
📐 Area
Square Millimeter, Square Centimeter, Square Meter, Square Kilometer, Hectare, Acre, Square Inch, Square Foot, Square Yard, Square Mile
🧪 Volume
Milliliter, Liter, Cubic Meter, US Gallon, UK Gallon, US Quart, US Pint, US Cup, Fluid Ounce, Cubic Inch, Cubic Foot
🏎️ Speed
Meters per Second, Kilometers per Hour, Miles per Hour, Knots, Feet per Second, Mach
⏱️ Time
Millisecond, Second, Minute, Hour, Day, Week, Month, Year
💾 Data
Bit, Byte, Kilobyte, Megabyte, Gigabyte, Terabyte, Petabyte
How to Use the Online Unit Converter
- 1Select a Conversion Category: Choose from eight categories: Length, Weight, Temperature, Area, Volume, Speed, Time, and Data Storage. Each category includes the most commonly used units. Quick conversion buttons below the converter let you jump to popular conversions instantly.
- 2Enter Your Value and Units: Type a number in the "From" field and select the source and target units from the dropdown menus. The result appears instantly in the "To" field as you type. The formula display shows the exact conversion ratio being applied.
- 3Copy, Swap, or Convert Again: Click the copy button to copy the result to your clipboard. Use the swap button to reverse the conversion direction. Change units or values at any time for instant new results. All conversions happen in your browser with no internet connection required.
Key Features
- -Eight Conversion Categories: Convert between units of length, weight, temperature, area, volume, speed, time, and data storage. Each category includes all commonly used units from both metric and imperial systems, covering over 60 individual units.
- -Instant Real-Time Results: Conversion results update as you type with no button press required. The formula display shows the exact conversion ratio, making it easy to understand the relationship between units and verify accuracy.
- -Precise Temperature Formulas: Temperature conversion uses proper formulas rather than simple multiplication factors. Celsius to Fahrenheit, Kelvin conversions, and all other temperature pairs are handled with mathematically correct formulas for accurate results.
- -Quick Conversion Shortcuts: Pre-built quick conversion buttons for the most popular conversions in each category, such as km to miles, kg to pounds, and Celsius to Fahrenheit. One click loads the conversion instantly.
- -Works Offline on Any Device: The converter runs entirely in your browser with no server requests. It works on mobile phones, tablets, and desktops without any app installation. All calculations happen locally for instant, reliable results.
Frequently Asked Questions
How do I convert kilometers to miles and other length units?
To convert kilometers to miles, multiply the kilometer value by 0.621371. For example, 10 km equals 6.21371 miles. Our unit converter handles this and all other length conversions automatically. Select the Length category, choose your source and target units, and the result appears instantly. We support millimeters, centimeters, meters, kilometers, inches, feet, yards, miles, and nautical miles.
What is the difference between metric and imperial unit systems?
The metric system uses base-10 units (meters, kilograms, liters) and is the standard measurement system used worldwide. The imperial system uses units like feet, pounds, and gallons, and is primarily used in the United States and a few other countries. Our converter handles both systems seamlessly, allowing you to convert between metric and imperial units for length, weight, volume, and more.
Is this online unit converter accurate and free to use?
Yes, our unit converter is completely free with no registration required. It uses precise conversion factors for all standard units and proper mathematical formulas for temperature conversions (not simple multiplication). All calculations happen in real-time in your browser, ensuring fast and accurate results. The converter works offline once the page is loaded, and no data is sent to any server.