Every unit conversion is the same problem: one number in, one number out, using a single magic ratio. Once you understand that, none of them are scary.
The golden rule
To convert between two units, you always go through a common base. For example, everything in our length converter is expressed in meters first — then it's simple arithmetic.
Common conversion facts
1 inch = 2.54 cm · 1 mile = 1.609 km · 1 kg ≈ 2.205 lb · 1 US gallon = 3.785 L · 0°C = 32°F · 1 GB = 1000 MB (or 1024 MiB — that's the classic confusion).
Why 1000 vs 1024 matters
Storage makers use 1000 (decimal) so 1 GB looks bigger; operating systems use 1024 (binary). That's why your "1 TB" drive shows only ~931 GB in Windows. Both are "correct".
Convert anything in seconds
Use our currency, temperature, data storage and energy converters — every one is free, instant, and runs in your browser.