Unit Converter
Convert between units across 7 categories. All conversions shown simultaneously.
Length
Unit converter online: convert length, weight, temperature, volume, and more instantly
Whether you are converting miles to kilometres for a travel app, Fahrenheit to Celsius for a recipe, or megabytes to gigabytes for storage calculations, this unit converter handles it instantly in your browser. It covers all the common measurement categories with precise conversion factors derived from official standards.
The tool supports both metric (SI) and imperial/US customary unit systems, and includes data storage units in both decimal and binary conventions. Select a category, pick your units, enter a value, and the result updates in real time with no button to click and no page reload.
Step-by-step guide
- 1Select a measurement category
Choose the type of measurement you want to convert: length, weight/mass, temperature, volume, area, speed, data, or another category. - 2Enter the value to convert
Type the numeric value you want to convert into the input field. - 3Choose the source unit
Select the unit you are converting from: for example, kilometres, pounds, or Fahrenheit. - 4Choose the target unit
Select the unit you want to convert to. The converted value updates instantly as you type or change units. - 5Copy or use the result
The converted value is displayed with appropriate precision. Click Copy to put it on your clipboard.
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Frequently Asked Questions
- What measurement categories does this tool support?
- The tool supports length (metres, feet, inches, miles, kilometres, etc.), weight/mass (kilograms, pounds, ounces, tonnes, etc.), temperature (Celsius, Fahrenheit, Kelvin), volume (litres, gallons, fluid ounces, etc.), area, speed, data storage, and more.
- How does temperature conversion work?
- Temperature conversion uses the standard formulas: Celsius to Fahrenheit is (C × 9/5) + 32, Fahrenheit to Celsius is (F - 32) × 5/9, and Kelvin is Celsius + 273.15.
- What is the difference between metric and imperial units?
- The metric system (SI) is the internationally standardised system using base-10 units like metres, kilograms, and litres. The imperial system uses units like feet, pounds, and gallons, and is primarily used in the United States and a few other countries.
- How precise are the conversions?
- Conversions use the exact NIST-defined conversion factors where available. Results are displayed to a sufficient number of significant figures for practical use. Very small or very large results are shown in scientific notation.
- Can I convert between metric and imperial units?
- Yes. The tool supports cross-system conversions such as miles to kilometres, pounds to kilograms, and gallons to litres.
- What data storage units are supported?
- Data storage units include bits, bytes, kilobytes, megabytes, gigabytes, terabytes, and petabytes, using both SI (decimal, base-1000) and IEC (binary, base-1024) conventions.
- Is this tool free?
- Yes, completely free with no account, no sign-up, and no usage limits.
- Does this tool work offline?
- All conversions are performed using JavaScript in your browser. Once the page is loaded you can use it without an internet connection.
AlteredIdea vs alternatives
vs server-side converters: AlteredIdea converts in your browser: your data never leaves your device.
vs writing scripts: Instant results, no coding needed.
vs paid tools: Completely free, no account required.