Data size converter
Data size converter, no network, no rounding surprises.
Runs on your device. The file is never uploaded.
Data size converter steps a value across six binary rows: B, KiB, KB, MB, GB and TB. KB and KiB both mean 1024 bytes here, and MB, GB and TB follow the same powers of 1024. Bits are deliberately absent, since a Kb row beside KB would be silently eight times wrong.
Questions
Which data units are supported?
Six: B, KB, MB, GB, TB and KiB. Bytes are the base, and every prefix here is binary. KB and KiB are both 1024 B, MB is 1048576, GB is 1073741824 and TB is 1099511627776. Both the from and to units must be picked, since neither has a default.
Does KB mean 1000 or 1024 bytes here?
1024. This table is binary throughout, which is what Windows and most developer tools mean when they print KB and MB. Drive manufacturers and macOS use the decimal reading, where a KB is 1000 bytes and a TB is a trillion, so a figure taken off a disk label will not match what you get here.
What is the difference between MB and MiB?
MiB is unambiguous, MB is not. The IEC prefixes Ki, Mi and Gi always mean powers of 1024, while KB and MB are used for both 1000 and 1024 depending on who wrote the number. This table treats them as the same thing: KB and KiB are both 1024 B, and MB is 1024 squared. Divide by 1000 yourself if you need the decimal reading.
Can I convert bits to bytes?
No, bits are deliberately absent. A Kb row sitting next to KB would differ by one letter and a factor of eight, and a slip between them is silently wrong rather than obviously wrong, so bits were kept out of this table. Divide by eight yourself if you are starting from a bit figure such as a network speed.
Why is KiB in the list but not MiB or GiB?
Because the table carries one IEC-named row and it is KiB, at 1024 B. There is no MiB, GiB or TiB entry. Since KB, MB, GB and TB already hold the binary values here, MB is numerically what MiB would be, so use those rows and read them as the IEC sizes.
Why did my value not parse?
It has to be a plain number, or you get "value must be a number". Take the unit out of the value field and pick it in the from dropdown instead. Large sizes work in scientific notation, so 1.5e9 is fine, and the answer prints as one line naming both units.