FORMAT DECISIONS
AVIF vs WebP vs PNG: which should a web image use?
No single format fits every image. Separate file size, reversible pixels, and recipient compatibility before you decide; it is more reliable than chasing the smallest file alone.
Key points
- AVIF, WebP, and PNG are delivery tradeoffs, not a simple size ranking.
- A quality value and true lossless are different concepts; high quality does not mean reversible pixels.
- Confirm where an image will open before deciding whether a fallback format is necessary.
Start with where the image is going, not with which format is smallest
The recipient determines the useful format range. For modern web delivery, AVIF or WebP may be worth evaluating. When images go to unknown software versions, older browsers, or external clients, keeping a compatible format matters more than one compression number.
One source image can reasonably produce two outputs: a modern web delivery and a broader fallback. That is not waste; it moves compatibility risk before publication.
What each format is solving for
AVIF suits modern delivery that benefits from efficient encoding and supports true lossless output. It is not a button that guarantees the smallest result for every image; content and settings still matter.
WebP covers common modern web needs in lossy and lossless modes, making it useful when balancing size, quality, and browser support. PNG remains a practical everyday lossless choice when a recipient requires PNG or compatibility comes first.
- Need reversible pixels: check the target format's lossless mode instead of only increasing quality.
- Need modern web delivery: test AVIF or WebP in the target browser and publishing path.
- Need broad compatibility or an existing PNG workflow: keep PNG, or use it as the fallback delivery.
Put the choice in a repeatable batch workflow
Set the source set, target format, and output directory clearly, then batch-process. ImgConvert lets a task use one shared format while an individual image can override it when there is a real exception.
For size-sensitive work, keep Skip larger outputs enabled. It does not promise a smaller file, but it avoids writing a larger candidate into the output directory.
Common questions
Is AVIF always smaller than WebP or PNG?
No. File size depends on image content, encoder, and settings. AVIF offers efficient encoding capability, not a size guarantee for every image.
Does quality 100 mean lossless?
No. Quality and lossless mode are separate encoding choices. Use a target format's lossless mode when pixels need to remain reversible.
Which fallback format should I keep?
It depends on the recipient. When compatibility is unknown, keeping the original PNG or JPEG is safer than deciding from file size alone.