Megabytes to kibibytes:
multiply by 976.5625

How many KiB are in a MB?

One megabyte is exactly 976.5625 kibibytes. A megabyte (MB) is 1,000,000 bytes in decimal units, and a kibibyte (KiB) is 1,024 bytes in binary units, so one MB divided by 1,024 bytes per KiB gives 976.5625.

The converter on this site treats MB as decimal, where 1 KB is 1,000 bytes. KiB, MiB and GiB are the binary units based on 1,024. Converting between the two systems is therefore a real calculation, not just a shift of the decimal point.

The MB to KiB formula

1. 1Write the size in MB.
2. 2Multiply by 976.5625.
3. 3Round to the precision you need, since the result is often a long decimal.
4. 4Check that the KiB figure is a bit under a thousand times the MB figure.

Chart: MB to KiB

Notice that the KiB number is always about 2.3 percent below a straight thousand-fold. That gap is the difference between 1,000 and 1,024.

Going back: KiB to MB

Reverse the process by multiplying kibibytes by 1,024 to get bytes, then dividing by 1,000,000. A 64 KiB buffer holds 64 × 1,024 = 65,536 bytes, which is 0.065536 MB. Developers meet round binary sizes like 64 KiB or 512 KiB in memory pages and cache sizes, while file listings from download sites often use MB.

Another useful pair to remember: 1 MiB is 1,024 KiB or 1,048,576 bytes, which is 1.048576 MB. So a '1 MB' limit that is actually enforced as 1 MiB lets a file of 1,048,576 bytes through.

More examples: downloads and memory sizes

Because the factor is not a round number, it helps to see a few more results. A 700 MB download is 700 × 976.5625 = 683,593.75 KiB, and a 4.7 MB image is 4,589.84375 KiB. In bytes these are 700,000,000 and 4,700,000, which divided by 1,024 give the same figures.

The reverse is just as common in software. A 512 KiB block holds 512 × 1,024 = 524,288 bytes, which is 0.524288 MB. If a developer says a limit is 512 KiB and a user reads it as 512 KB, the user expects about 12,000 bytes fewer than what is allowed.

As a rule, remember the order of the units. A kibibyte is 1,024 bytes, a kilobyte is 1,000 bytes, and a megabyte is a thousand kilobytes. Write the byte count of every figure first and the confusion disappears, because bytes are the common ground that both systems share.

Common mistakes when converting MB to KiB

• Using 1,000 as the factor. That would convert MB to KB, not KiB.
• Using 1,024 as the factor. That converts MiB to KiB; MB to KiB is 976.5625.
• Mixing MB and MiB in the same comparison, which makes two equal files look different.
• Dividing instead of multiplying. A kibibyte is smaller than a megabyte, so the KiB figure must be larger.