Petabytes to Gigabytes (PB to GB)

1 petabyte equals 1,000,000 gigabytes exactly.

1 petabyte = 1,000,000 gigabytes

How to convert petabytes to gigabytes

To convert petabytes to gigabytes, multiply the number of petabytes by 1,000,000. This factor is exact. To go the other way, multiply gigabytes by 0.000001.

gigabytes = petabytes × 1,000,000

Example: 10 petabytes = 10,000,000 gigabytes.

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

Petabyte (PB)

ComputingCurrent unit

1,000 terabytes (10¹⁵ bytes). The scale of large data centers.

Peta entered the SI in 1975, when the General Conference on Weights and Measures approved peta and exa in its Resolution 10. A petabyte is 10 to the fifteenth bytes, or 1,000 terabytes, and the word is formed by attaching that prefix to byte, a term Werner Buchholz coined in June 1956 as a deliberate respelling of bite. The binary counterpart is the pebibyte: the IEC amendment published in January 1999 added pebi and exbi to the earlier binary names.

Decimal units dominate at this size: hard drives, SSDs, optical discs and network contracts all use powers of 1,000, and macOS, iOS, Android and Ubuntu follow suit. As an example of the size, one petabyte is about 2,000 years of MP3-encoded music at roughly one megabyte per minute. Binary use of the P symbol is less common than for smaller prefixes.

1 petabyte = 1×10¹⁵ bytes (exactly).

Sources: Wikipedia: Petabyte; BIPM: SI prefixes; Wikipedia: Binary prefix

Gigabyte (GB)

ComputingCurrent unit

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

Related conversions

See all digital storage units.