Convert BMP to AVIF

Turn old BMP images into AVIF files, the smallest modern format.

Runs on your device. Your files are never stored.

Short answer

To convert BMP to AVIF, add your files to FileFleet, adjust the quality if you like, and download the AVIF files, zipped if there are several. It runs in your browser, so nothing is uploaded. In our test, a 2400 × 1350 photo went from 9.27 MB to 12 KB as AVIF.

Price
Free
Account
None needed
Your files
Never stored
Limits
No daily limit, no watermark
You get
AVIF images, zipped if there are several
Works on
Phones and computers

BMP vs AVIF

AVIF makes the smallest possible web image from a BMP, often well under one percent of the original size.

FeatureBMPAVIF
Full nameWindows BitmapAV1 Image File Format
Introduced19852019
CompressionUsually noneLossy or lossless
TransparencyRarely supportedYes
AnimationNoYes
Best forOld Windows software that needs raw pixelsThe smallest files for websites
Opens inWindows and most image apps; not accepted by most websitesCurrent Chrome, Firefox, Edge and Safari; many apps can’t open it yet

What happens to file size

Measured with FileFleet’s own converter at its default quality (85%), November 2026. Your files will differ, but the direction is usually the same.
Test imageBMPAVIFChange
A 2400 × 1350 photo9.27 MB12 KB819× smaller
A 1440 × 860 website screenshot3.54 MB24 KB148× smaller

About the two formats

BMP

BMP stores every pixel with no compression at all, so even simple images take megabytes. It’s mostly found in old software, scanners and exports.

AVIF

AVIF uses compression from the AV1 video codec and usually makes the smallest image files of any common format. Browser support is broad, but desktop apps are still catching up.

How to convert BMP to AVIF

  1. 1Add your BMP files.
  2. 2Adjust the quality if you like.
  3. 3Download the AVIF files.

Questions

Do my files get uploaded?

No. BMP to AVIF runs entirely in your browser, so your files never leave your device. Close the tab and they're gone.

Is it really free?

Yes. No account, no daily limits and no watermark on your files.

Will the image look different?

At the default quality the difference is very hard to see, even though the file is a tiny fraction of the BMP.

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