BMP to PNG
Convert huge uncompressed bitmaps into compact lossless PNGs.
About this converter
BMP in, PNG out โ same pixels, dramatically smaller file. Drop several at once, take a ZIP. The conversion is lossless: PNG stores exactly what the BMP held, minus the wasted space.
Why BMPs are enormous (and PNG isn't)
BMP dates from early Windows, when disks were small but CPUs were smaller โ so it usually stores pixels raw, three bytes per pixel, no compression at all. A 1920ร1080 screenshot is 6 MB as BMP; the same pixels as PNG, which compresses losslessly, might be 100 KB. Nothing visual differs โ PNG simply doesn't write the redundancy down. BMPs still arrive daily from MS Paint habits, old scanner software, industrial cameras and legacy exports, and converting them is the rare free lunch: strictly smaller, pixel-identical, universally supported. The one direction that surprises people is needing to go BACK โ some embroidery machines, label printers and retro tools accept only BMP, which is why PNG to BMP exists next door. Photos (as opposed to graphics) can go smaller still as JPG, at a slight, usually invisible cost; How to reduce image file size without wrecking it explains when each choice wins.
Frequently asked questions
Is BMP to PNG really lossless?
Yes โ both formats store exact pixels; PNG just compresses the redundancy away. The image is identical to the last pixel.
How much smaller will the PNG be?
Screenshots and graphics: often 10โ50ร smaller. Photographs: 2โ5ร. BMP stores raw bytes, so anything with repetition compresses dramatically.
Why does anything still produce BMP files?
Legacy: MS Paint defaults of old, industrial and scientific cameras, scanner bundleware. The format survives because it's trivially simple to write.
Can I convert several BMPs at once?
Yes โ drop the lot, download individually or as a ZIP, all processed on your device with nothing uploaded.