Convert BMP to PNG — lossless, and much smaller
This is one of the rare conversions with no downside: PNG stores exactly the same pixels as a BMP, but compressed. Because BMP is normally uncompressed — a legacy of early Windows — even simple images occupy megabytes they don’t need, and PNG’s lossless compression reclaims that space without changing a single pixel. Screenshots from old software, Paint drawings, and exports from legacy scanners or lab equipment are the usual suspects. Everything runs in your browser: the BMP is decoded by the browser’s native decoder and re-encoded to PNG locally, so nothing is uploaded and the tool keeps working even with your connection switched off.
How it works
- Drop your .bmp files below.
- Press Start — it’s lossless, so there are no options.
- Save the finished PNG files.
Frequently asked questions
Is BMP to PNG really lossless?
Yes, completely. PNG’s compression is lossless by design, so the PNG decodes to the exact same pixels as the original BMP. It is the same image in a dramatically more sensible container.
How much smaller will the PNG be?
It varies with content: screenshots and graphics with flat areas often shrink by 80–95%, while noisy photographic bitmaps compress less. Since the source BMP is usually uncompressed, some meaningful saving is almost guaranteed.
Why do programs still produce BMP files?
BMP is trivially simple to write, so old Windows software, scanner drivers, and embedded or lab equipment still emit it. It remains fine as an intermediate format — just a poor one for storing or sharing.
Is my data transmitted anywhere during conversion?
No. Decoding and encoding both happen inside your browser on your own hardware. There is no server component, no upload, and consequently no file size limit beyond your device’s memory.