Convert BMP to PNG Online Free

BMP files are huge because they are uncompressed. AllConvert converts BMP to PNG with zero quality loss — typically shrinking the file by 50–80% — right in your browser.

Why convert BMP to PNG?

BMP stores every pixel uncompressed, so even a modest screenshot can weigh several megabytes. PNG stores the exact same pixels with lossless compression — the image is bit-for-bit identical, but the file is typically 50–80% smaller. PNG is also far more widely supported on the web, in chat apps and in email, where many services reject or mangle BMP attachments.

Truly lossless

Unlike converting to JPG, converting BMP to PNG loses nothing: every pixel is preserved exactly. That makes it the right choice for screenshots, diagrams, scans and any image you may want to edit later. If the image is a photograph and you want the smallest possible file, converting to JPG or WEBP shrinks it much further at a small quality cost.

Where do BMP files come from?

Old versions of Microsoft Paint, Windows screenshot tools, scanners and many legacy programs still produce BMP files. Converting them to PNG modernizes the file without touching the image itself.

How to convert

1. Open AllConvert and drop your BMP file onto the page.
2. Select PNG from the format dropdown on the file card.
3. Click Convert and download your result.

The entire process runs locally in your browser. Nothing is uploaded, and it works on desktop and mobile, in Chrome, Firefox, Safari, and Edge.