Gigabytes to Kilobytes (GB to kB)
1 gigabyte equals 1,000,000 kilobytes exactly.
How to convert gigabytes to kilobytes
To convert gigabytes to kilobytes, multiply the number of gigabytes by 1,000,000. This factor is exact. To go the other way, multiply kilobytes by 0.000001.
kilobytes = gigabytes × 1,000,000
Example: 10 gigabytes = 10,000,000 kilobytes.
Decimal prefixes (kB, MB, GB) are powers of 1,000; binary prefixes (KiB, MiB, GiB) are powers of 1,024. Storage makers use decimal; Windows reports binary but labels it GB.
About these units
Gigabyte (GB)
1,000,000,000 bytes (decimal). Storage manufacturers and phone makers use this definition.
The gigabyte is where the decimal-versus-binary dispute turned into lawsuits. Drive makers advertise capacity in decimal units, so a 500 GB drive holds 500 billion bytes, but Windows reports sizes in binary units and shows about 465.7 of what it labels GB for the same drive. Early challenges against Western Digital and Seagate were settled, with Western Digital adding disclaimers that usable capacity may differ from the advertised figure.
A 2019 lawsuit was decided in the manufacturers' favor, with the court relying on the decimal definition. For scale, one gigabyte holds roughly an hour of standard-definition video at 2.2 Mbit/s. A single-layer DVD+R holds about 4.7 GB and a single-layer Blu-ray about 25 GB. RAM is still often sized in binary gigabytes, which the IEC would call gibibytes.
1 gigabyte = 1,000,000,000 bytes (exactly).
Sources: Wikipedia: Gigabyte; Wikipedia: Binary prefix; Wikipedia: Gibibyte
Kilobyte (kB)
1,000 bytes in the SI (decimal) definition. Older software and Windows sometimes use KB to mean 1,024 bytes; see kibibyte.
Few units have had two meanings for so long. By the mid-1960s most computers used binary addressing, so memory sizes came in powers of two and engineers borrowed kilo to mean 1,024. IBM documentation for the System/360 in 1964 used an uppercase K for 1,024. Hard disk makers took a different path from the start. The IEC later settled the question: kilobyte, symbol kB, means 1,000 bytes, and 1,024 bytes is a kibibyte.
Floppy disks show the muddle. The Shugart SA-400 of 1976 held 109,375 bytes unformatted and was advertised as 110 Kbyte, the decimal way, while a 1978 Tandon double-density disk held 368,640 bytes, or 360 times 1,024, and was sold as 360 KB. Windows still divides by 1,024, so a 65,536-byte file appears as 64 KB there, while Mac OS X Snow Leopard and later would call it 66 kB. A kilobyte is also tiny: Edgar Allan Poe's The Cask of Amontillado is 12,843 bytes.
1 kilobyte = 1,000 bytes (exactly).
Sources: Wikipedia: Kilobyte; Wikipedia: Binary prefix; NIST: Prefixes for binary multiples
Related conversions
- Kilobytes to gigabytes (reverse)
- Gigabytes to bytes
- Gigabytes to megabytes
- Gigabytes to terabytes
- Gigabytes to bits
- Gigabytes to petabytes
- Gigabytes to kibibytes
- Gigabytes to mebibytes
- Gigabytes to gibibytes
- Gigabytes to tebibytes
- Gigabytes to kilobits
- Gigabytes to megabits
- Gigabytes to gigabits
- Bytes to kilobytes
- Megabytes to kilobytes
- Terabytes to kilobytes
- Bits to kilobytes
- Petabytes to kilobytes
- Kibibytes to kilobytes
- Mebibytes to kilobytes
- Gibibytes to kilobytes
- Tebibytes to kilobytes
- Kilobits to kilobytes
- Megabits to kilobytes
- Gigabits to kilobytes
See all digital storage units.