Data Size Converter
Convert between data storage units.
How to use the Data Size Converter
- Type the figure into the Value box; the result updates as you type, with no button to press.
- Set From and To with the KB, MB, GB and TB drop-downs. The page opens on MB to GB.
- Read the converted figure below, rounded to six decimal places and labelled with the unit.
Every step here is 1024, not 1000
This converter multiplies and divides by 1024 at each level, the way Windows reports file and drive sizes. The strict names for units counted that way are KiB, MiB, GiB and TiB.
Why a new drive looks smaller than the box says
Drive makers sell capacity in powers of 1000 while your system may report it in powers of 1024. Nothing is missing: the same bytes, described two ways.
| Sold as | In 1024-based units |
|---|---|
| 256 GB | 238.42 GB |
| 500 GB | 465.66 GB |
| 1 TB | 931.32 GB |
| 2 TB | 1.82 TB |
| 4 TB | 3.64 TB |
Frequently asked questions
How many MB in a GB?
1,024 MB, and that is the figure this converter uses. Windows counts the same way, while macOS and drive makers treat a gigabyte as 1,000 MB.
Why does my drive show less space than advertised?
Manufacturers count in powers of 1,000 while operating systems count in powers of 1,024. A drive sold as 1 TB shows as about 931 GB, and the gap widens with capacity.
How many GB are in a TB?
1,024 GB here, since the converter counts in binary units. A drive sold as 1 TB holds a trillion bytes, about 931 GB the same way.
Can I convert bytes or bits?
No, the drop-downs offer KB, MB, GB and TB only. At 8 bits to the byte, a 100 Mbps line moves about 12.5 MB per second.
Why does my figure show six decimal places?
Results are rounded to six decimals, so 1 KB in GB still shows as 0.000001 rather than being flattened to zero.