| Kilobytes (KB) | Megabytes (MB) |
|---|---|
| 1 | 0.001 |
| 2 | 0.002 |
| 3 | 0.003 |
| 4 | 0.004 |
| 5 | 0.005 |
| 6 | 0.006 |
| 7 | 0.007 |
| 8 | 0.008 |
| 9 | 0.009 |
| 10 | 0.01 |
| Kilobytes (KB) | Megabytes (MB) |
|---|---|
| 12 | 0.012 |
| 15 | 0.015 |
| 20 | 0.02 |
| 25 | 0.025 |
| 30 | 0.03 |
| 40 | 0.04 |
| 50 | 0.05 |
| 60 | 0.06 |
| 75 | 0.075 |
| 100 | 0.1 |
Kilobytes in upload limits
Job portals, exam forms and visa sites often set limits such as 100 KB for a photo or 500 KB for a signed document. When a limit is written in kilobytes and your file is listed in megabytes, multiply the megabytes by 1,000 to compare: a 0.3 MB scan is 300 KB and passes a 500 KB cap with room to spare.
If a file is over the limit, the fix is to make it smaller rather than to argue with the units. Compress image to 100 KB and compress PDF to 200 KB aim at those common caps directly.
Decimal and binary kilobytes
The SI prefix kilo means 1,000, so a decimal kilobyte is 1,000 bytes. Older software adopted 1,024 bytes because it is a power of 2 and close to 1,000; the IEC later named that unit the kibibyte, KiB. Both are in daily use, and the difference at this level is only 2.4%, but it doubles in size by the time you reach gigabytes.
Uppercase or lowercase k makes no difference in practice here. The SI symbol is a lowercase k, but KB with a capital K is the most common spelling for kilobytes.
Do
- Compare sizes in bytes when a limit is tight
- Use the same unit the form or service states
Avoid
- Rounding 0.98 MB to 1 MB and assuming it fits a 1,000 KB cap
- Mixing kilobits (kb) and kilobytes (KB) in one calculation
Other conversions near this one
Going the other way is MB to KB, and for larger files the MB to GB converter takes the next step up.
KB to MB questions
Does a megabyte hold 1,000 or 1,024 kilobytes?
1,000 KB in decimal units and 1,024 KB in binary units. Web forms and phones usually mean decimal; Windows File Explorer shows binary values.
Is 500 KB bigger than 1 MB?
No. 500 KB is half a megabyte in decimal units, or about 0.49 MB in binary units.
How do I check whether a file is under 2 MB?
Look at the size in bytes in the file's properties, then compare it with 2,000,000. Byte counts have no prefix, so they avoid the decimal and binary question altogether.
What is 250 KB in MB?
0.25 MB in decimal units. In binary units it is about 0.244 MB.
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