Unit Converter: 323 Units Across 43 Categories
Convert between length, mass, pressure, temperature, electrical, and other scientific units. Instant conversion online.
Try the free online tool mentioned in this guide:Unit Converter
Why a unit converter?
Scientific and engineering work involves many units:
- Metric vs imperial — kilometers, miles, liters, gallons.
- Specialized units — pascals, joules, amperes.
- Easy mistakes — confusing units costs money (Mars probe lost to unit error).
A converter eliminates guessing and ensures accuracy.
Unit categories
Fundamental: - Length (meter, foot, mile, kilometer) - Mass (kilogram, pound, ton, ounce) - Time (second, minute, hour, day) - Temperature (Celsius, Fahrenheit, Kelvin)
Derived: - Area, volume, pressure, energy, power, force, velocity - Electrical (ampere, volt, watt, ohm) - Thermal (specific heat, thermal conductivity) - Polymer and materials science units
Common conversions
- 1 mile = 1.609 km
- 1 pound = 0.454 kg
- 1 gallon = 3.785 liters
- 1 inch = 2.54 cm
- 32°F = 0°C
- 1 kilowatt = 1000 watts
Conversion workflow
1. Select category — length, mass, energy, etc. 2. Enter value — e.g., 5 miles. 3. Select units — from miles, to kilometers. 4. See result — 8.05 km. 5. Copy — grab the result for use.
Frequently asked questions
Is temperature conversion T(K) = T(°C) + 273.15 correct?
Yes, that's the standard formula. Converters handle it automatically.
What about currency or crypto?
This tool focuses on scientific units. Exchange rates change constantly; use a currency converter for that.
Can I convert between unusual units?
323 units across 43 categories covers most scientific needs. Niche units may not be included.