Data Size Converter

What digital data units measure

They give an amount of information or the speed at which it is transferred. The smallest unit is the bit (0 or 1), and a byte (B) equals 8 bits. It is not an SI base unit but is widely used with SI prefixes.

Main units and where they are used

• KB, MB, GB, TB – file sizes, memory and drives.
• Kibibyte (KiB = 1024 B), mebibyte (MiB), gibibyte (GiB) – binary units often used by operating systems.
• Mbit/s and Gbit/s – internet speed (bits, not bytes).
• Decimal units (1 KB = 1000 B) are used by drive makers and networks.

Common pitfalls

The two most frequent: kb vs KB (bits vs bytes) and 1000 vs 1024. An internet speed of 100 Mbit/s means roughly 12.5 MB/s, since 100 / 8 = 12.5. A 1 TB drive you bought can show up in an operating system as about 931 GiB, because 10^12 bytes / 2^30 is about 931.3. This is not a defect or a trick, just a difference in definitions.