Storage Unit Converter
Convert between bits, bytes, KB, MB, GB, TB, and PB using both decimal (1000-based) and binary (1024-based) definitions.
Binary: 1 KB = 1,024 bytes — how operating systems typically report file and memory sizes.
Decimal vs binary units
Storage sizes are written two ways. Decimal (SI) units go up in steps of 1,000: 1 KB = 1,000 bytes and 1 GB = 1,000,000,000 bytes. Binary units go up in steps of 1,024: 1 GiB = 1,073,741,824 bytes. Drive makers use decimal units, while many operating systems divide by 1,024 but still show the result as “GB”. This converter labels both as KB, MB and GB, and the mode you choose sets which definition applies.
- A 1 TB drive holds 1,000,000,000,000 bytes, which is 931.32 binary gigabytes, so a computer shows it as about 931 GB.
- Network speeds use bits, not bytes: 100 megabits is 12.5 megabytes, so a 100 Mbps connection moves at most 12.5 MB a second.
How to use the Storage Unit Converter
- Type a number in the Amount field.
- Choose the unit it is in from the Unit menu (bit, byte, KB, MB, GB, TB, or PB).
- Pick a Definition: Binary (1024) or Decimal (1000).
- Read the converted value for every unit in the result cards; the card for your input unit is highlighted.
Example: Why a 500 GB drive shows about 465 GB
Enter 500000000000 as the Amount, choose byte, and select Binary (1024). The GB card shows 465.661287 and the TB card shows 0.454747, while the byte card shows 5.0000e+11. Switch to Decimal (1000) and the GB card reads 500.
Questions about the Storage Unit Converter
- Why do some results appear as 5.0000e+11?
- Values of one billion or more, and values smaller than 0.000001, are shown in scientific notation with four decimal places. 5.0000e+11 means 5 x 10^11, or 500,000,000,000.
- Can I convert from decimal units to binary units in one step?
- Not directly; the input and all results use the same Definition. To compare, enter the size in bytes and toggle between Binary (1024) and Decimal (1000).
- How are bits handled?
- 1 byte is always 8 bits, in both modes. The 1000 or 1024 factor only applies between byte, KB, MB, GB, TB, and PB.
- How many decimals are shown?
- Up to six decimal places, using your browser's number formatting, so separators can differ by locale.
- Why does my 1 TB drive show about 931 GB?
- The drive holds 1,000,000,000,000 bytes (decimal terabyte). Your computer divides by 1,024 three times instead of 1,000, giving about 931.32, and still labels it GB.
- Is 1 KB 1,000 or 1,024 bytes?
- Both definitions are in use. Under the SI standard 1 KB is 1,000 bytes and 1,024 bytes is properly called a kibibyte (KiB), but many operating systems still show 1,024-byte units as KB. Pick the mode that matches where your number came from.