Modernize legacy BMP images into optimized PNG format instantly.
BMP (Bitmap, also called Device Independent Bitmap) is a raster format created by Microsoft for early versions of Windows around 1990. Most BMP files store pixel data with little to no compression, so file sizes scale directly with image dimensions and color depth rather than actual visual complexity. This simplicity made BMP easy for any program to read and write reliably, but it also means a BMP is often 5-10 times larger than an equivalent JPG or PNG. It's still occasionally produced by legacy Windows tools, screenshot utilities, and some scientific or industrial imaging software that prioritize a simple, uncompressed structure.
PNG (Portable Network Graphics) is a lossless raster format released in the mid-1990s as a royalty-free successor to GIF, after a licensing dispute over the LZW compression algorithm. It compresses images with the DEFLATE algorithm, the same method used by ZIP archives, so every pixel is preserved exactly with no generation loss on repeated saves. PNG also supports a full 8-bit alpha channel for smooth, partial transparency, unlike GIF's binary on/off transparency. These properties make it the standard choice for screenshots, logos, icons, and any graphic with sharp edges, flat colors, or text that needs to stay perfectly crisp.
PNG provides lossless compression like BMP, but creates much smaller files while adding support for transparency.
Yes, PNG files load much faster and are supported everywhere.
Yes, this tool is completely free with no registration, no watermark, and no conversion limit.
No, the conversion happens locally in your browser using JavaScript. Your files are never uploaded to any external server.
There's no fixed limit enforced by the tool since everything runs in your browser rather than on a server.
For most everyday uses, the visual difference is negligible.