Unit Converter
Convert between units for length, weight, temperature, area, volume, speed, pressure, and data.
Quick reference
| 1 Millimeter (mm) = | 0.1 Centimeter (cm) |
| 1 Millimeter (mm) = | 0.001 Meter (m) |
| 1 Millimeter (mm) = | 0.000001 Kilometer (km) |
| 1 Millimeter (mm) = | 0.0393700787402 Inch (in) |
The formulas behind the conversions
Length, weight, area, volume, speed, pressure and data units all convert through one fixed factor each way. Temperature is the exception because its scales start at different zeros, so an offset is involved:
- °F = °C × 9/5 + 32
- K = °C + 273.15
Data storage follows binary multiples (1 KB = 1,024 B), matching what operating systems report, not the decimal 1,000 used by drive marketing.
Two steps, every conversion
- 1
Pick the measurement family, type the value, and the result appears instantly in the target unit.
- 2
Swap the direction with one click when you need the reverse — factors are exact in both directions.
How this converter is designed
Eight measurement families
Length, weight, temperature, area, volume, speed, pressure, and data storage, with each family carrying its usual units from millimeters to miles and bytes to petabytes.
Exact conversion factors
Every unit pair converts by official definitions, with a foot exactly 0.3048 meters and a pound exactly 453.59237 grams, so results match standards rather than approximations.
Frequently asked questions
How does the unit converter work?
Select a category, source/target units, and enter a value. Conversion uses standard formulas instantly. Temperature uses specific non-linear formulas.
Is temperature conversion accurate?
Yes — uses exact formulas: °F = (°C × 9/5) + 32, K = °C + 273.15. Not simple multiplication because temperature scales have different zero points.
What data storage units are used?
Binary (IEC) prefixes: 1 KB = 1024 B, 1 MB = 1024 KB. Used in computing for RAM and file sizes. Some manufacturers use decimal (1 KB = 1000 B).
Can I use scientific notation?
Yes — enter values like 1.5e6 for 1,500,000. Results display appropriately for the magnitude.
Related tools
What Is a Unit Converter?
A unit converter translates a measurement from one unit into its equivalent in another, covering the eight categories people handle every day: length, weight, temperature, area, volume, speed, pressure, and data storage. Each conversion follows the official definition of the units involved, and temperature is handled as a proper offset conversion, so Celsius, Fahrenheit, and Kelvin never go out of step. Instead of memorizing constants — that a foot is 0.3048 meters, or that a pound is 453.59237 grams — you type one value and read the answer instantly. Students, cooks, travelers, and anyone who juggles metric and imperial in the same week will find a use for it.
What this tool can do
- 📐 Length: from millimeters and meters to inches, feet, yards, and miles.
- ⚖️ Weight: milligrams to metric tonnes, including ounces and pounds.
- 🌡️ Temperature: Celsius, Fahrenheit, and Kelvin converted with correct offset arithmetic.
- 📏 Area: square meters, square kilometers, square feet, acres, and hectares.
- 🧊 Volume: milliliters, liters, cubic meters, US gallons, fluid ounces, and cups.
- 🚀 Speed and pressure: km/h, mph, and knots; pascals, bars, PSI, and atmospheres.
- 💾 Data storage: bytes through terabytes using binary multiples of 1,024.
When would you use it
- 🍳 Halving a recipe measured in cups and ounces while your kitchen scale reads grams.
- ⛽ Comparing fuel consumption in kilometers per liter and miles per gallon during a trip.
- 🛋️ Converting room dimensions between meters and feet before ordering furniture.
- 🔬 Finishing a homework or lab problem that mixes unit systems.
Conversion happens on your device with no uploads and nothing saved, so unit values you enter cannot be read by anyone. Note that data sizes use binary multiples (1,024 bytes per kilobyte), the convention your operating system uses, rather than the decimal 1,000 — so do not be surprised when a ‘1 GB’ drive shows up as less in your file manager.