Data storage converter

Bits, bytes, KB, MB, GB and TB converted in real time, in both the decimal system (×1000) and the binary system (×1024) used by operating systems.

Enter an amount to see every conversion.

Decimal (×1000)Binary (×1024)
bitbyte
KBKiB
MBMiB
GBGiB
TBTiB
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Why does a 1 TB drive show "only" 931 GB?

It's not a defect and nobody is cheating you — it's a units issue. Hard drive and SSD manufacturers use the decimal system, where 1 TB = 1,000,000,000,000 bytes. Windows, however, measures space with the binary system (a Windows "GB" is really a gibibyte, i.e. 1,073,741,824 bytes): divide a trillion bytes by that figure and you get exactly 931 GiB. All the space is there — only the ruler used to measure it changes. macOS and Linux, on the other hand, have shown decimal GB since 2009, matching the number on the box.

Bits vs. bytes: watch out for internet plans

A byte is made of 8 bits, and the difference trips up plenty of people shopping for an internet plan: "gigabit" fiber runs at 1 gigabit per second, which is about 125 megabytes per second. A 4 GB movie, under ideal conditions, therefore downloads in roughly half a minute — not in 4. Rule of thumb: network speeds are quoted in bits (Mbps, Gbps), file sizes in bytes (MB, GB). This converter puts them side by side so you never mix them up.