Because of irregularities in definition and usage of the kilobyte, the exact number could be any one of the following:
- 1,152,921,504,606,846,976 bytes - 1024 times 1024 times 1024 times 1024 times 1024 times 1024, or 260. This is 1024 times a petabyte. This is the definition used in computer science and computer programming
- 1,000,000,000,000,000,000 bytes - or 10 18.
See integral data type.
A zettabyte is 1024 times an exabyte.
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 exbibyte. (Gi) This naming convention has not been widely accepted.