File size calculator

Convert KB to MB Instantly

Type a kilobyte value and get the megabyte equivalent immediately in both conventions: binary (1,024 KB = 1 MB, the one forms and operating systems use) and decimal (1,000 KB = 1 MB, the marketing one).

1,024 KB = 1 MB (binary) | 1.024 MB (decimal)

Arithmetic only | the calculator never reads or uploads a file.

Photo and scan sizes are usually quoted in KB while attachment limits arrive in MB, so the conversion direction matters daily: a 4,800 KB photo against a 5 MB ceiling is fine in binary terms (4.69 MB) and fine in decimal too (4.8 MB), but a 5,200 KB file fails both.

Quick reference: 100 KB = 0.098 MB, 500 KB = 0.488 MB, 1,024 KB = 1 MB, 2,048 KB = 2 MB, 5,120 KB = 5 MB, 10,240 KB = 10 MB in binary terms.

If a conversion shows your file over a limit, the fix is a measured re-compress to a KB target, which this suite does entirely in your browser with a live achieved-size readout.

Is 1,000 KB one MB or not?

In decimal marketing terms yes, in binary system terms no (1 MB = 1,024 KB). Upload validators use binary, so trust the binary column for limits.

Why do small KB values show as 0.0x MB?

Because a megabyte is a thousand-plus kilobytes. Form photos in the 20 to 200 KB range are fractions of an MB, which is exactly why portals quote KB.

Does converting units change my file?

No. Units are labels for the same byte count | only a re-compress changes actual size.

How it works

Type the KB value in the box.
Read both MB conventions instantly.
Check the number against an MB-stated attachment limit.
Need the file smaller? Open a KB-target preset from the chips below.

Related sizes and converters

MB to KB Reduce in MB Compress to 2 MB Image Compressor

Frequently asked questions