File size

File size measures the size of a computer file. Typically it is measured in bytes with a prefix. The actual amount of disk space consumed by the file depends on the file system.

The maximum file size a file system supports depends on the number of bits reserved to store size information and the total size of the file system. For example, with FAT32, the size of one file cannot be equal or larger than 4 GiB.

Some common file size units are:

• 1 KiB = 1,024 bytes

• 1 MiB = 1,048,576 bytes^[1]

• 1 GiB = 1,073,741,824 bytes^[2]

= 1,099,511,627,776 bytes^[3].

Conversion table

Name	Symbol	Binary Measurement	Decimal Measurement	Number of Bytes	Equal to
KiloByte	KB	210	103	1,024	1,024 bytes
MegaByte	MB	220	106	1,048,576	1,024 KB
GigaByte	GB	230	109	1,073,741,824	1,024 MB
TeraByte	TB	240	1012	1,099,511,627,776	1,024 GB
PetaByte	PB	250	1015	1,125,899,906,842,624	1,024 TB
ExaByte	EB	260	1018	1,152,921,504,606,846,976	1,024 PB
ZettaByte	ZB	270	1021	1,180,591,620,717,411,303,424	1,024 EB
YottaByte	YB	280	1024	1,208,925,819,614,629,174,706,176	1,024 ZB

References

1. ^ 2^20 = 1 048 576
2. ^ 2^30 = 1 073 741 824
3. ^ 2^40 = 1 099 511 627 776