Convert AVIF to BMP
Free, unlimited AVIF to BMP conversion that runs entirely inside your browser. No upload, no sign-up, no watermark.
Convert your AVIF files to BMP
or drop them here, or paste with Ctrl+V · files never leave your device
Settings
Nothing queued yet. Add as many files as you like — everything runs on your own device.
Nothing is uploaded
Conversion runs in your browser. Your files never touch a server, so there is no copy of them to leak.
No sign-up, no watermark
No account, no email, no daily limit, and nothing stamped across your image.
Batch and folders
Drop a hundred files at once and download the results as a single ZIP.
Works offline
Once this page has loaded you can disconnect entirely and it still works.
This converter turns AVIF images into BMP files without uploading anything. The conversion runs inside this page using your own device's processor, so your photos never leave your computer — there is no server copy to worry about, no queue to wait in, and no limit on how many files you convert.
AVIF is a modern format built on the AV1 video codec, producing the smallest files of any widely supported image format. All current browsers decode AVIF. Outside the browser, support is still thin — which is usually why you need it converted. BMP, by contrast, strong on Windows, weak everywhere else, and never used online.
AVIF turns up when you save an image from a site that has modernised its delivery. Browsers handle it fine, but nearly everything else — desktop editors, office software, print services — does not. BMP is the pragmatic choice when the file has to leave the browser.
How to convert AVIF to BMP
- Add your AVIF files. Drag them onto the box above, click to browse, or paste an image straight from your clipboard. You can add as many at once as you like.
- Adjust the settings if you need to. The defaults suit most images. BMP is lossless, so there is no quality setting to adjust. Pick a background colour if your image has transparent areas.
- Download the BMP file. Each file gets its own download button as soon as it finishes, and you can pull the whole batch down as a single ZIP.
What changes when you convert AVIF to BMP
Every format conversion involves trade-offs, and vague tools hide them. Here is exactly what happens to your image in this particular conversion.
- BMP has no transparency channel, so any transparent areas are filled with a solid colour. White is used by default and you can pick a different colour before converting — this is the single most common surprise when going from AVIF to BMP.
- BMP is lossless, so nothing further is lost — but it also cannot restore detail that AVIF already threw away. Expect the BMP file to be considerably larger than the original despite containing the same visible image.
- BMP stores every pixel uncompressed, so expect a very large file — often ten times the size of the AVIF you started with. That is normal and not a fault of the conversion.
What happens to the file size
Measured, not estimated: two 1200 x 800 pixels references — a photograph and a flat-colour graphic — put through this converter.
| Reference image | As AVIF | As BMP | Change |
|---|---|---|---|
| Photograph | 104 KB | 2.75 MB | +2598% |
| Graphic with text | 4 KB | 2.75 MB | +79548% |
Yours will differ: size depends more on what is in the picture than on the formats involved.
About AVIF (AV1 Image File Format)
AVIF is a modern format built on the AV1 video codec, producing the smallest files of any widely supported image format.
Where you probably got it: Downloaded from a modern website that serves next-gen images.
Strengths
- Typically 30–50% smaller than JPG at visually identical quality
- Handles transparency, HDR and wide colour gamut
- Royalty-free and supported in all current browsers
Limitations
- Encoding is computationally expensive — noticeably slower than JPG or PNG
- Very little support outside browsers: most desktop and print software cannot open it
- Can smear fine texture at aggressive settings
About BMP (Windows Bitmap)
BMP is Microsoft’s raw, uncompressed bitmap format — every pixel stored literally, with no compression at all.
Support: Strong on Windows, weak everywhere else, and never used online.
Strengths
- Dead simple and completely lossless
- Read by even the most primitive Windows tooling and embedded devices
- No decoding overhead, which some industrial and medical systems require
Limitations
- Enormous files — often 10–20x larger than a PNG of the same image
- Poorly supported on the web; browsers can display it but nobody serves it
- No transparency in the widely supported 24-bit form, so transparent areas are filled with a solid colour
Is it safe to convert AVIF online?
Here, yes — and you can check rather than trust. Open your browser’s developer tools, switch to the Network tab and convert a AVIF file: no request carrying your image is made. Disconnect from the internet after this page has loaded and the converter still works, which would be impossible if a server were doing the conversion.
That is worth verifying wherever you convert, because most online converters do upload, and AVIF files are so often personal photos and documents people would not hand to a stranger. Once a file is on somebody else’s server you are relying on a privacy policy rather than on anything you can observe. We wrote up how to tell a safe converter from a risky one in more detail.
Frequently asked questions
How do I convert AVIF to BMP?
Drag your AVIF file onto the box above, or click it to browse. The conversion starts immediately in your browser and the BMP download appears within a second or two for most images. You can drop in a whole folder of files at once and download them together as a ZIP.
Are my AVIF files uploaded to a server?
No. The conversion happens locally in your browser, so your files are never transmitted anywhere — the tool even works with the network disconnected once the page has loaded. That is also why there is no file size or file count limit: nothing costs us anything per conversion. The practical ceiling is your own device's memory, which on a phone means very large images may fail.
Does AVIF to BMP keep transparency?
It cannot — BMP has no transparency channel at all. Transparent pixels are filled with a background colour, which defaults to white. Use the background colour picker before converting if you need black or a brand colour instead. If you need to keep the transparency, convert to PNG or WebP rather than BMP.
Will converting AVIF to BMP reduce the quality?
No further quality is lost — BMP is lossless. Bear in mind it also cannot recover detail the original AVIF had already discarded, and the resulting file will be noticeably larger.
What is the difference between AVIF and BMP?
AVIF is a modern format built on the AV1 video codec, producing the smallest files of any widely supported image format. BMP is Microsoft’s raw, uncompressed bitmap format — every pixel stored literally, with no compression at all. In practice the choice comes down to compatibility: all current browsers decode AVIF. Outside the browser, support is still thin — which is usually why you need it converted. Meanwhile strong on Windows, weak everywhere else, and never used online.