Convert BMP to PNG

A BMP stores every pixel raw — the format dates from when compression cost more CPU than disks cost money, and that trade flipped decades ago. PNG holds the identical pixels, losslessly, in a fraction of the space. This is the rare conversion with no catch: nothing is discarded, the file just stops being enormous.

  1. Your BMP files

    Drop your BMP files here

    BMPPNGJPGWebP

    Your files are never uploaded.

  2. What you want back

  3. Your files

How to convert BMP to PNG

  1. Add your BMP files

    Old scans, MS Paint art, exports. They are read by your browser and never uploaded.

  2. Leave it on PNG

    Pixel-for-pixel identical, lossless. JPG is there for photos where smaller matters more.

  3. Save the PNGs

    One by one, or everything as a zip.

What you get

Identical pixels, a fraction of the bytes

PNG's compression is lossless — the picture that comes out is the picture that went in, pixel for pixel. Screenshots and graphics routinely shrink to a tenth of the BMP; even photographs lose a quarter or more.

A format the modern web accepts

Plenty of forms, chats and CMSes refuse BMP outright or mangle it. PNG is accepted everywhere an image can go, so the file stops being the obstacle.

Old archives, in one pass

The folder of scans from 2003 converts as a batch, every file keeping its name, out as a single zip. This is the page for finally shrinking that directory.

Your files are never uploaded

The conversion happens in this page — relevant when the BMPs are old family scans, and the alternative is pushing a gigabyte of them through someone's server.

Questions about BMP and PNG

Is anything lost converting BMP to PNG?
No. Both formats store exact pixels; PNG just compresses them losslessly on the way in and restores them exactly on the way out. This conversion is a free lunch — the only cost is the moment of CPU it takes.
How much smaller will the PNG be?
It depends on the image. Screenshots, diagrams and anything with flat colour: often a tenth of the BMP or less. Photographs and scans: usually to between half and three-quarters of the original, because photographic noise compresses poorly. If a photo needs to be genuinely small, JPG on this page trades a little fidelity for a much bigger saving.
Why do BMP files even exist any more?
Old software, old scanners, some Windows workflows and a few industrial tools still write them, because BMP is trivially simple to produce. Nothing is wrong with the files — they are just paying for that simplicity in size, forever, until converted.
Does it handle odd BMPs — 8-bit, huge ones?
The browser's decoder reads the common shapes: the 24- and 32-bit files nearly everything writes, and palette-based ones. A BMP it cannot read fails on its own row with a message rather than taking the batch down. Truly enormous files are limited by your machine's memory.
Is it free, and is my file uploaded?
Free, no account, no limit. Runs entirely in your browser. Your files are never uploaded.

If the result needs to fit under an upload limit, resize it to a size in KB. Photos from an iPhone rather than the web? That is HEIC to JPG. Or see the rest of the image tools.