KB to MB: Kilobytes to Megabytes Converter
With the decimal and binary conventions both shown, because the answer really does depend on which one you mean.
Enter a number.
Ranking pages disagree with each other on this, right now. Checked in August 2026, one widely-ranked converter states that 1 MB is 1,024 KB while another states that 1 KB is 0.001 MB. Both are internally consistent; they are using different conventions and mostly not saying which. This tool makes you pick, and defaults to decimal because that is what storage is sold in.
Why there are two answers
The SI prefix kilo means exactly 1,000, so a kilobyte under the decimal convention is 1,000 bytes. Early computing borrowed the prefix for 2 to the power 10, which is 1,024, because it was conveniently close. The two meanings have coexisted ever since.
binary: 1 MiB = 1,024 KiB
The IEC defined kibibyte, mebibyte and gibibyte to name the binary units unambiguously. Almost no consumer software uses those names, which is why the ambiguity survives. Prefix detail is on the metric prefixes chart.
Conversion table
| Kilobytes | MB (decimal, /1000) | MB (binary, /1024) | Difference |
|---|---|---|---|
| 100 KB | 0.100 | 0.098 | 2.4% |
| 500 KB | 0.500 | 0.488 | 2.4% |
| 1,000 KB | 1.000 | 0.977 | 2.4% |
| 1,024 KB | 1.024 | 1.000 | 2.4% |
| 5,000 KB | 5.000 | 4.883 | 2.4% |
| 10,000 KB | 10.000 | 9.766 | 2.4% |
| 100,000 KB | 100.000 | 97.656 | 2.4% |
| 1,000,000 KB | 1000.000 | 976.562 | 2.4% |
The gap compounds at each step. It is 2.4 percent at the kilobyte, 4.9 percent at the megabyte, 7.4 percent at the gigabyte and 10.0 percent at the terabyte, which is why a 1 TB drive shows as about 931 GB.
A different question people ask here
Some searches for this phrase are really about reducing an image or PDF file size rather than converting a number. This page converts units. It can't compress a file, and any tool claiming to convert a photo from KB to MB is either resizing it or padding it.
Common questions
Is 1 MB 1024 KB?
It depends which convention you are using, and that's the real answer. Under the binary convention used by most operating systems, yes. Under the decimal convention used by storage manufacturers and the SI, 1 MB is 1,000 KB. The difference is 2.4 percent at this step.
What is bigger, KB or MB?
A megabyte. It is either 1,000 or 1,024 times larger than a kilobyte depending on convention, but either way MB is the bigger unit.
How many KB are in 1 MB of data?
1,000 under the decimal convention, 1,024 under the binary one. Storage is sold in decimal; operating systems have historically reported binary.
Which convention should I use?
Decimal if you are checking an advertised capacity or a download size. Binary if you are reconciling what your operating system reports. This tool shows both.
Related converters and guides
Sources
- The binary prefixes kibi, mebi and gibi are defined by the International Electrotechnical Commission, not by the SI. The decimal prefixes kilo, mega and giga are SI and are always powers of 1,000. That split is the source of the disagreement described on this page.
- NIST Guide to the SI, Appendix B: Conversion Factors. National Institute of Standards and Technology. Source for every conversion factor on this page, and for which factors are exact rather than rounded.