Unit Converter
Last updated: June 1, 2026Length, weight, volume, speed & more.
Unit Converter is a free online calculator to length, weight, volume, speed & more. It runs entirely in your browser, so your files never leave your device — nothing is uploaded. There's no sign-up, no watermark, and it works on any modern browser on desktop or mobile.
How to use Unit Converter
The Unit Converter handles length, weight, volume, area, speed, data and time in one place. Pick a category, choose your 'from' and 'to' units, and convert instantly with accurate factors. Free and runs entirely in your browser.
- 1Choose a category (length, weight, etc.).
- 2Pick the units to convert from and to.
- 3Enter a value to see the result.
Many categories
Length, weight, volume, area, speed, data and time in one tool.
Accurate
Uses precise conversion factors for metric and imperial units.
Free & private
Runs on your device with no sign-up.
Unit Converter — frequently asked questions
What units can I convert?
Length (mm–miles), weight (mg–pounds), volume, area, speed, digital storage (B–TB) and time, with both metric and imperial units.
How do I convert km to miles?
Choose Length, set 'from' to kilometers and 'to' to miles, then type the value — 1 km ≈ 0.621 miles.
Is it free?
Yes, completely free.
Share this tool
Send it to someone who needs it or save the link for later.
More calculators
View allCountdown to Date
Live countdown to any event.
Number to Words
Spell out any number in English.
Aspect Ratio Calculator
Resize keeping the same ratio.
Time Duration Calculator
Hours and minutes between two times.
Currency Converter
Convert between 30+ currencies with live rates.
Sales Tax Calculator
Add or remove sales tax from any price.