KB to MB Converter — Kilobytes to Megabytes
A KB to MB converter turns kilobytes into megabytes — the unit pair you meet in file upload limits, email attachments, scanned documents and web assets.
Quick answer: Divide kilobytes by 1,024 for binary megabytes (MiB) or by 1,000 for decimal megabytes. 500 KB is 0.488 MiB or 0.5 MB decimal; 1,024 KB is exactly 1 MiB.
The two lines are the same file — only the definition of “GB” differs. This 2.4% gap per step is why a 1 TB drive shows 931 GiB in Windows.
| KB | MB |
|---|---|
| 0.5 | 0.000488281 |
| 1 | 0.000976563 |
| 2 | 0.00195313 |
| 5 | 0.00488281 |
| 10 | 0.00976563 |
| 50 | 0.0488281 |
| 100 | 0.0976563 |
| 500 | 0.488281 |
| 1,000 | 0.976563 |
| 1 MB (binary) | 1,024 KB = 1,048,576 bytes |
|---|---|
| 1 MB (decimal) | 1,000 KB = 1,000,000 bytes |
| 1 KB | 1,024 B (binary) or 1,000 B (decimal) |
| Where it matters | Upload limits, email attachments, retouching exports, web page weight |
Upload limits are usually decimal
When a form says “maximum 2 MB”, the server almost always compares against 2,000,000 bytes (decimal), while your file manager shows sizes in KiB. A 1.95 MiB file (about 2,045 KB binary) is still under a decimal 2 MB limit — 2,045,056 bytes versus 2,000,000. Re-encode or crop images when a rejection message appears, rather than trusting the rounded label.
Scanned documents and images
A 300 dpi colour scan of an A4 page lands between 500 KB and 2.5 MB depending on compression; a phone photo at 12 MP is 2–5 MB. Knowing that 1 MB is roughly 1,000 KB makes it easy to plan email attachments: five 800 KB scans are about 4 MB, comfortably inside most 25 MB limits.
When to use this calculator
- Checking whether a file fits an upload or attachment limit quoted in MB.
- Converting export sizes from image editors that report KB.
- Budgeting page weight: 300 KB of images per page is 0.29 MB.
- Comparing scanned PDF sizes against a form's kilobyte limit.