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KB to MB Converter

Updated July 2026 · Written & fact-checked by the NumberBench editorial team · How we calculate

Convert kilobytes to megabytes. Enter a size in KB and choose decimal (1000) or binary (1024); you get the selected result, the other convention alongside it, and the size in bytes.

Example: with Size in KB 1500 · Convention Decimal / SI (1 MB = 1000 KB) → Result: 1.5 MB (decimal, 1000).

  • Other conventionBinary mode: 1.465 MiB
  • In bytesAbout 1,500,000 bytes (1 KB = 1,000 bytes)

Computed by the calculator below using its default values. Change any input to see your own numbers.

Result—
Other convention—
In bytes—

Decimal (SI): 1 MB = 1000 KB. Binary (IEC): 1 MiB = 1024 KB. File managers and RAM lean binary; storage and network specs lean decimal. The data is the same either way.

Your next stepTake megabytes up to gigabytes →

The 1000 versus 1024 split

A kilobyte is either 1000 bytes (decimal, SI) or 1024 bytes (binary), and the same fork carries up to the megabyte. Under decimal, 1 MB = 1000 KB; under binary, 1 MiB = 1024 KB. So 1500 KB is 1.5 MB the decimal way or about 1.465 MiB the binary way. The choice depends on who is counting.

Historically the 1024 value came first, because memory is organized in powers of two, and kilobyte was borrowed loosely to mean 1024. To remove the ambiguity, the IEC introduced kibibyte (KiB) and mebibyte (MiB) for the binary values, leaving KB and MB for the clean decimal thousands. Both remain in wide use, which is why this tool shows each.

How it’s calculated

Decimal (SI): MB = KB ÷ 1000. Binary (IEC): MiB = KB ÷ 1024. Both are computed; the selected convention is the main result and the other is shown for comparison. The byte total uses the decimal definition, 1 KB = 1000 bytes.

The input KB is read as decimal kilobytes for the byte count. Which convention is right depends on context: decimal for storage and transfer specs, binary for file managers and memory.

KB to MB in both conventions

KBMB (decimal 1000)MiB (binary 1024)
1,00010.9766
1,0241.0241
1,5001.51.4648
2,0482.0482
5,00054.8828

Decimal: MB = KB/1000. Binary: MiB = KB/1024.

Common mistakes

  • Treating KB to MB as a single fixed factor rather than 1000 or 1024.
  • Labeling a 1024-based result MB when it is really MiB.
  • Mixing kilobytes (KB) with kilobits (Kb), which differ by a factor of 8.
  • Rounding away the small 2.4 percent gap that separates the two conventions.

Frequently asked questions

How many KB are in an MB?

1000 under the decimal (SI) standard, or 1024 under the binary standard. Decimal calls it MB; binary calls it MiB (mebibyte).

Is a kilobyte 1000 or 1024 bytes?

Both definitions are used. The decimal SI kilobyte is 1000 bytes; the binary kibibyte (KiB) is 1024 bytes. Context decides which applies.

Why do file sizes differ between my file manager and the download page?

Download pages often quote decimal MB (1000-based) while file managers may report binary MiB (1024-based), so the numbers differ slightly for the same file.

What is the difference between KB and Kb?

KB is kilobytes (storage); Kb is kilobits (data rate). One byte is 8 bits, so they differ by a factor of 8. Do not mix them.