KB to MB Converter
Type a size in kilobytes and read it in megabytes. The default divisor is 1,024, and ticking the SI box changes it to 1,000.
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Created by the Reeliy Editorial Team. Last updated: Oct 19, 2026
How many kilobytes are in a megabyte?
There are 1,024 kilobytes in a megabyte when sizes are counted in powers of two, and 1,000 kilobytes when the SI meaning of the prefixes is used. Both appear in everyday life, often under the same abbreviation.
binary: MB = KB ÷ 1,024
SI: MB = KB ÷ 1,000
The converter opens in binary mode. The Use SI standard checkbox changes the divisor to 1,000 and recalculates immediately from the figure already typed.
Difference between KB and MB
The kilobyte is a small unit: an e-mail without attachments, a plain-text page or an icon file is typically a handful of kilobytes. The megabyte is a thousand (or 1,024) times larger and is the natural unit for photographs, music tracks and application downloads.
A note on spelling. The official SI symbol for kilo is a lowercase k, so a thousand bytes is written kB, while the capital KB is traditionally the binary kilobyte of 1,024 bytes. The IEC name for the latter is kibibyte (KiB). This tool follows the common practice of writing KB for both and lets the checkbox decide the meaning.
How to convert KB to MB
- Enter the number of kilobytes.
- Leave the SI box clear for 1,024 per MB, or tick it for 1,000 per MB.
- Read the megabytes in the lower box.
Results are rounded to four decimal places and printed without separators. Emptying the input keeps the previous answer on screen rather than clearing it.
Example: a 3,500 KB photo
Binary: 3,500 ÷ 1,024 = 3.41796875, shown as 3.418 MB. SI: 3,500 ÷ 1,000 = 3.5 MB. A smaller attachment of 750 KB comes to 0.7324 MB in binary terms and 0.75 MB in SI terms.
KB to MB conversion table
| Kilobytes (KB) | MB, binary (÷ 1,024) | MB, SI (÷ 1,000) |
|---|---|---|
| 100 | 0.0977 | 0.1 |
| 256 | 0.25 | 0.256 |
| 500 | 0.4883 | 0.5 |
| 512 | 0.5 | 0.512 |
| 1,000 | 0.9766 | 1 |
| 1,024 | 1 | 1.024 |
| 2,048 | 2 | 2.048 |
| 5,000 | 4.8828 | 5 |
| 10,000 | 9.7656 | 10 |
| 102,400 | 100 | 102.4 |
For the opposite direction, see the MB to KB converter.
Common mistakes
- Confusing kilobytes with kilobits. A lowercase b means bits, so 1,000 Kb is 125 KB. The bits to bytes converter helps when a figure comes in bits.
- Expecting small files to show a meaningful value. A 40 KB icon is only 0.0391 MB in binary counting, and anything under roughly 0.05 KB (about 51 bytes) rounds to 0 MB because the answer is limited to four decimals.
- Switching conventions halfway. If you start with the SI box ticked, stay with it for the whole calculation, otherwise totals will not match.
Frequently asked questions
How many KB are in 1 MB?
1 MB equals 1,024 KB under the binary convention and 1,000 KB under SI.
How do I convert KB to MB?
Divide the kilobytes by 1,024 for binary megabytes or by 1,000 for SI megabytes. For example, 2,560 KB is 2.5 MB in binary and 2.56 MB in SI.
Is KB the same as kB?
Strictly no. The SI symbol kB means 1,000 bytes, while KB has long been used for 1,024 bytes. Many programs print KB for either, so check which meaning applies.
Why do two programs show different sizes for one file?
One may divide by 1,024 and the other by 1,000. Over two steps (bytes to KB to MB) the gap grows to about 4.9%.
References
Cite this converter and page
If you use this page in your work, you can cite it as:
Reeliy Editorial Team. (2026). KB to MB Converter. Reeliy. https://reeliy.com/converters/convert-kb-to-mb“KB to MB Converter.” Reeliy, 2026, https://reeliy.com/converters/convert-kb-to-mb.