Are my images uploaded to a server?

No. The entire conversion runs inside your browser using the HTML5 Canvas API. Your BMP file never leaves your device.

Why is the PNG so much smaller than the original BMP?

BMP stores raw uncompressed pixel data, which makes files very large. PNG uses lossless compression (DEFLATE) that can reduce file size by 50–90% for typical images while preserving every pixel perfectly.

Does the PNG preserve all the colors from the BMP?

Yes. The conversion is lossless — every pixel from the BMP is captured exactly and stored in the PNG without any quality loss.

Does the tool support 32-bit BMP files with transparency?

Yes. If the BMP contains an alpha channel (32-bit BGRA), the browser will decode it correctly and the resulting PNG will preserve that transparency.

Is there a file size limit?

The practical limit is your browser's available memory — typically several hundred megabytes. Very large BMP files may be slow to process on low-end devices.

What if the image looks wrong after conversion?

Some non-standard BMP variants (e.g., OS/2 BMPs or exotic color depths) may not decode correctly in all browsers. If you encounter issues, try opening the BMP in an image editor first and re-saving it as a standard 24-bit BMP.

BMP to PNG Converter

Name: BMP to PNG Converter
Availability: InStock
Author: Nham Vu

Upload a BMP file and download a lossless PNG — converted instantly in your browser with no file upload.

Upload BMP

Click or drag a BMP here

BMP files only — converted to lossless PNG in your browser

Preview (PNG output)

Upload a BMP to see the PNG preview

Conversion happens instantly, entirely in your browser

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Summary