Kilobyte (kB)

Definition

One thousand bytes (10³ B) in the decimal (SI) convention.

History

The kilobyte took the metric kilo prefix for a thousand, but in computing it was often used loosely for 1024 bytes. The IEC later defined the kibibyte for the binary value to remove the ambiguity.

Where it is used

Kilobytes measure small files and text documents; in strict decimal use a kilobyte is exactly one thousand bytes.

Typical uses include small files, documents.

Conversion pages

These pages convert kilobyte to or from another unit in digital storage.

• Kilobyte to megabyte

Other Digital storage units

• Byte (B)
• Bit (bit)
• Megabyte (MB)
• Gigabyte (GB)
• Terabyte (TB)
• Gibibyte (GiB)
• Mebibyte (MiB)
• Tebibyte (TiB)

Sources

• IEC 80000-13 IEC 80000-13 (quantities and units — information science); NIST on binary prefixes · Dataset reviewed Nov 11, 2026