How it's calculated
MB = KB ÷ base (base = 1024 binary or 1000 decimal)
KB = kilobytes, MB = megabytes, base = bytes per step. Binary (1024) is the RAM/OS convention; decimal (1000) is the drive-marketing convention.
Common values
| KB | MB (binary, 1024) | MB (decimal, 1000) |
|---|---|---|
| 1,024 KB | 1 MB | 1.024 MB |
| 2,048 KB | 2 MB | 2.048 MB |
| 5,000 KB | 4.883 MB | 5 MB |
| 10,240 KB | 10 MB | 10.24 MB |
Common questions
Is 1 MB equal to 1000 or 1024 KB?
Both are used. Storage and networking labels use 1,000 KB, while Windows and memory use 1,024 KB, which is why a drive looks smaller than advertised.
Why does my hard drive show less space than the label?
Drives are sold in decimal units of 1,000, but the OS reports in binary units of 1,024, so a 1 TB drive shows about 931 GB.