Unit Converter
Convert between metric, imperial, and other units — instantly.
100% in-browser — no data sent anywhere
Select units and enter a value to convert
Quick Reference
About Unit Conversion
The metric system (SI) is used by most countries worldwide, with units like meters, kilograms, and Celsius. The imperial system uses feet, pounds, and Fahrenheit, and is primarily used in the United States.
Temperature conversions use formulas (e.g., °F = °C × 9/5 + 32), while most other conversions are simple multiplication by a conversion factor. All calculations happen instantly in your browser.
Supported categories
Temperature
Celsius, Fahrenheit, and Kelvin with precise formula-based conversion.
Length
Millimeters to miles — full metric and imperial length units.
Weight
Milligrams to stone — all common mass and weight units.
Speed
m/s, km/h, mph, and nautical knots for any velocity conversion.
Data Size
Bytes to petabytes — binary-standard data size conversions.
Metric & Imperial
Seamlessly convert between the two most common measurement systems.