Because of irregularities in definition and usage of the kilobyte, the exact number could be any one of the following:
- 1,099,511,627,776 bytes - 1024 times 1024 times 1024 times 1024, or 240. This is 1024 times a gigabyte. This is the definition used in computer science and computer programming
- 1000000000000 bytes - or 10 12.
See integral data type.
A petabyte is 1024 times an terabyte.
To clarify the meaning(1) above, the International Electrotechnical Commission (IEC), a standards body, in 1997 proposed short unions of the International System of Units (SI) prefixes with the word "binary." Thus meaning (1) would be called a tebibyte. (Gi) This naming convention has not been widely accepted.