Unit Converter

How to use the Unit Converter

1. Choose a category: length, weight/mass, temperature, area, volume, speed, time or digital storage.
2. Enter the value and pick the “From” and “To” units. Use Swap to reverse them.
3. Set the number of decimal places you want. The result updates immediately, together with a table of the value in every unit of that category.
4. For digital storage, switch between decimal (kB = 1,000 B) and binary (KiB = 1,024 B) prefixes.

Good to know

• Conversion factors use exact definitions where they exist: 1 in = 0.0254 m, 1 lb = 0.45359237 kg, 1 US gallon = 3.785411784 L, 1 mph = 0.44704 m/s.
• Temperature conversions go through kelvin because Celsius and Fahrenheit have offsets, not just scale factors. Values below absolute zero are rejected.
• Time uses a 365.25-day year and a 30.4375-day average month. Real calendar months and years vary; use the Age Calculator for calendar dates.
• Volumes named gallon, quart, pint, cup, fluid ounce and spoon are US customary; the imperial (UK) gallon is listed separately. Weight and mass are treated as equivalent at Earth’s surface.
• Results are cleaned of floating-point noise and rounded to the decimal places you choose (0–12), with trailing zeros removed. A tiny non-zero result is shown in scientific notation instead of 0.

Examples

Length

5 km = 3.107 mi (rounded to 3 decimals). 1 inch is exactly 2.54 cm.

Temperature

98.6 °F = 37 °C. −40 °C and −40 °F are the same temperature.

Digital storage

1 GB (decimal) = 0.931323 GiB. 1 GiB = 1,024 MiB, while 1 GB = 1,000 MB.

Frequently asked questions