Convert BMP to AVIF
Drop BMP files and download them as AVIF. AVIF supports transparency but BMP files have none, so the output is fully opaque; use the crop or background tools if you need cut-outs. Conversion runs on your device, so large batches finish in seconds and nothing is uploaded.
How to use the BMP to AVIF
- Drop or paste your BMP files (up to 200).
- Set the AVIF quality (90 is visually lossless).
- Click Convert to AVIF.
- Download each file or all as a ZIP.
Why convert BMP to AVIF?
BMP is the uncompressed Windows bitmap format. Files are very large (3 bytes per pixel) but trivially simple, which is why some legacy software, embedded systems and wallpaper settings still require it.
AVIF is based on the AV1 video codec and typically beats WebP by another 20–30% at the same quality, with transparency and HDR support. Browser support is universal since 2024, but many image editors, email clients and upload forms do not accept it yet.
What changes in the conversion
BMP is lossless and AVIF is lossy: the conversion trades a little detail for a much smaller file. At quality 90 the difference is invisible for photos; for text and line art keep quality high or prefer a lossless target. AVIF supports transparency but BMP files have none, so the output is fully opaque; use the crop or background tools if you need cut-outs.
BMP vs AVIF at a glance
| BMP | AVIF | |
|---|---|---|
| Compression | lossless | lossy |
| Transparency | no | yes |
| Animation | no | yes |
| Typical size | very large | smallest of all |
| Opens in | Windows and most editors | modern browsers; limited desktop software |
How it works on your device
Your browser decodes the BMP file into raw pixels, draws them onto a canvas and asks its built-in encoder to write AVIF (Chrome and Edge; Firefox and Safari cannot yet write AVIF and the tool will say so). Nothing is sent to a server, which is why there is no file-size limit beyond your device's memory and no queue.
Need a different pair? See all image converters or use the general converter.
Frequently asked questions
Does converting BMP to AVIF lose quality?
BMP is lossless and AVIF is lossy: the conversion trades a little detail for a much smaller file.
Is there a limit on file size or number of files?
Up to 200 files per batch and no fixed size limit; processing happens in your browser.
Are my images uploaded?
No. The conversion runs on your device and works offline after the page loads.
Privacy
This tool runs entirely inside your browser using WebAssembly and the Canvas/File APIs. Your files are never uploaded to ToolFlint or any third party; you can verify this in your browser's network tab or by switching to airplane mode after the page loads. Read how we process files.
Last updated 2026-09-23.