Terabytes to Petabytes (TB to PB)

1 terabyte equals 0.001 petabytes exactly.

1 terabyte = 0.001 petabytes

How to convert terabytes to petabytes

To convert terabytes to petabytes, multiply the number of terabytes by 0.001. This factor is exact. To go the other way, multiply petabytes by 1,000.

petabytes = terabytes × 0.001

Example: 10 terabytes = 0.01 petabytes.

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

Terabyte (TB)

ComputingCurrent unit

1,000 gigabytes (10¹² bytes), the capacity of a typical modern hard drive.

Tera comes from the SI prefix for 10 to the twelfth, so a terabyte is one million million bytes. Computer memory is binary, so the prefixes were once used for powers of two, which caused confusion. IUPAC proposed binary prefixes such as kibi, mebi and gibi in 1995, and the IEC adopted them in December 1998 and published the standard in January 1999. The tebibyte is the binary counterpart, about 9 percent larger than the terabyte.

Hitachi introduced the first one-terabyte consumer hard drive in 2007. For scale, one terabyte is about 20 standard Blu-ray discs or 213 DVDs. The mismatch shows at this size: a drive sold as 1 TB may be reported as about 931 GB, because Windows uses the historic binary convention. macOS and iOS did the same until Mac OS X 10.5 Leopard and iOS 10, then switched to powers of 10.

1 terabyte = 1,000,000,000,000 bytes (exactly).

Sources: Wikipedia: Terabyte; Wikipedia: Binary prefix; NIST: Prefixes for binary multiples

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

Related conversions

See all digital storage units.