AVIF is a next-generation format with the highest compression efficiency available. Current browsers open AVIF, but support in programs and services is uneven.
BMP is Windows' basic bitmap that stores pixels as they are, without compression. When you convert AVIF to BMP, you can open it in more places, a solid background replaces transparency and the file grows. See the comparison below for what changes.
This converter reads the file itself to confirm it is AVIF, then converts it to BMP right in your browser. Your image is never uploaded.
AVIF vs BMP: what's the difference?
| Item | AVIF | BMP |
|---|---|---|
| Compression | Lossy or lossless | None (uncompressed) |
| Transparent background | Yes | No |
| Animation | Yes | No |
| Introduced | 2019 | 1990 |
| Support in programs and upload forms | limited | broad |
| Shown directly in browsers | Yes | Yes |
| Photo file size (JPG = 1) | about 0.5× | about 12× |
What is AVIF?
AVIF is an image format released in 2019 that builds on the still-image technology of the AV1 video codec. At the same quality it can be around 50% smaller than JPG, so websites sensitive to file size are adopting it quickly.
What is BMP?
BMP is a bitmap format from Windows that mostly stores pixel values as they are, without compression. Its simple structure makes it easy for programs to read, but the files are so large that it is rarely used on the web.
What changes when you convert AVIF to BMP
Transparent areas are filled with the background color you choose
BMP can't represent transparency. Transparent and semi-transparent areas are composited onto the background color in the options (white by default), so pick a matching color first if the image will be used on a dark screen.
Quality doesn't improve, but it doesn't get worse either
Information lost when AVIF was saved can't be recovered. BMP is lossless, so it keeps the image exactly as it is now and later edits and saves add no further degradation. File size will grow, though.
Moving images keep only their first frame
BMP can't hold animation. If your AVIF file is animated, only the first frame is converted.
With no compression, the file size grows a lot
BMP stores pixels as they are. A 1920×1080 image becomes about 6MB, so unless equipment or software requires BMP, another format is recommended.
BMP has no quality setting
BMP is none (uncompressed), so the quality slider doesn't apply. Instead, when converting from AVIF you can manage file size by resizing (exact width and height, or a percentage).
How the file size changes
For the same photo, BMP is much larger than AVIF (roughly 24× or so). This is for photos; for simple images such as logos and screenshots, PNG can actually come out smaller.
BMP opens in more places
Support for AVIF in programs, document tools and upload forms is limited, while BMP is broad. If you need to upload somewhere AVIF wouldn't open, try again after converting.
When to convert
- You need to upload to a program, messenger or upload form that can't open AVIF
- You need to feed legacy equipment or embedded software that only reads BMP
- You're preparing an image for typical BMP uses (input for legacy equipment and software, simple image-processing exercises)