Unit Converter
A fast, private unit converter. Pick your units, type a value, and the conversion appears instantly — in either direction. Everything runs on your device, so nothing you enter is ever uploaded.
- 🔒 100% private — no uploads
- 🆓 Free, no watermark
- 📱 Works on any device
How to convert
- 1
Choose your units
The tool opens on the most common pairing. Change either unit from its dropdown, or hit the swap button to flip the direction.
- 2
Type a value
Enter a number in either box. The other side updates instantly as you type — convert either way without pressing a button.
- 3
Copy or compare
Copy the result to your clipboard, or scan the common-values table below for quick at-a-glance conversions.
Why use Unit Converter?
100% private
Every conversion is computed locally in your browser. Nothing you enter ever leaves your device.
Instant & two-way
Results update live as you type, in either direction — no “convert” button and no page reloads.
Accurate
Conversions use exact, standards-based factors, so you get the same answer a trusted reference would.
Works on any device
No install and no account — it runs in any modern browser on desktop, tablet or phone.
One converter, every everyday unit
Length, weight, temperature, area, volume, speed, data storage and fuel economy — pick a category, choose any two units and convert in either direction as you type. Conversions use exact, standards-based factors (an inch is exactly 2.54 cm; a foot exactly 0.3048 m), so the only rounding is the decimals you keep.
Metric and imperial, side by side
Most conversions you’ll actually need cross the metric–imperial border: recipes in ounces, heights in feet, forecasts in Fahrenheit, road signs in km/h. The common-values table under the converter covers the usual suspects at a glance, and the dedicated pages for popular pairs (cm→inches, kg→lbs, °C→°F) go deeper with formulas and examples.
Frequently asked questions
What units does the unit converter support?
It covers the common unit units (mm, cm, m, km, in, ft, yd, mi and others). Choose any two from the dropdowns and convert between them instantly.
Does anything get uploaded to a server?
No. The conversion runs entirely in your browser with JavaScript — nothing you type is uploaded, stored or logged, and it keeps working offline once the page has loaded.
Is it free?
Yes — completely free, with no account, no watermark and no limits on how much you convert.