Data Storage Converter
How it works
Every value is turned into bytes first — multiplying by the entered unit's power of the chosen base — and then divided back out by each unit's own power of that same base. That is one exponent per unit rather than a formula per pair, and it is also why switching the base recomputes every figure on the page: the byte count itself never changes, only how it is grouped back into KB, MB, GB and the rest.
Byte is treated as the 0th power of the base (so it is identical under either setting), KB the 1st power (1024 or 1000), MB the 2nd, and so on up to PB at the 5th. The two bases only agree at the byte level; everything above it drifts further apart the higher the unit.
Frequently asked questions
Why are there two different answers for the same value?
Because "kilo" means two different things here. Memory is addressed in powers of two, so operating systems count 1024 bytes to a KB, 1024 KB to a MB, and so on — base 1024. Drive manufacturers advertise capacity in the everyday decimal sense, 1000 bytes to a KB — base 1000. Neither is wrong; they are counting the same bytes in different bases, and the gap grows at every step up.
Why does a "1TB" drive show up as about 931GB?
The drive was measured and labelled in base 1000 (1TB = 1,000,000,000,000 bytes), but your operating system reports its size in base 1024. Divide that same byte count by 1024 four times instead of 1000 four times and you get roughly 931 — nothing is missing from the drive, the two sides of the same box are just counting differently.
Are KiB and MiB the "correct" names for the binary versions?
Technically yes — KiB, MiB, GiB and so on are the unambiguous binary-only names, while KB, MB and GB are officially defined as the decimal (base 1000) units. Almost nobody actually types "KiB" in everyday use, though, so this tool keeps the familiar KB/MB/GB naming for both bases and lets you pick which base is active instead of doubling every unit on the page.