Image to WebP Converter
Converted on a canvas in your browser. Nothing is uploaded.
The image to WebP converter re-encodes an image as WebP using the browser’s own encoder, and shows the size change so you can judge whether the trade was worth it. Everything happens on a canvas locally. The file is never uploaded.
How it works
The image is drawn to a canvas at its native dimensions, then exported with toDataURL at the chosen quality. This is lossy re-encoding: the original compression is undone when the image is decoded, and new compression is applied on export.
- WebP typically produces files 25 to 35 percent smaller than JPEG at comparable quality.
- Transparency is preserved, which is WebP’s advantage over JPEG.
- Quality below about 70 shows visible artefacts on photographs; 80 to 90 is the usual working range.
- Re-encoding an already-compressed JPEG compounds the loss, because the artefacts of the first encode are treated as image detail by the second.
Examples
A photograph at default quality
Input
A 480 KB JPEG
Quality
85%
Result
Roughly 300 KB: about 37 percent smaller
Typical for a photograph. The saving comes from WebP’s better entropy coding rather than from discarding more detail.
A flat-colour PNG
Input
A 40 KB PNG logo
Quality
85%
Result
Often larger than the original
Lossy WebP is poor at flat colour with hard edges, which is exactly what PNG is good at. For logos and screenshots, keeping the PNG is usually better.
Frequently asked questions
Why did my PNG get bigger when converted to WebP?
Because lossy compression is the wrong tool for flat colour. PNG uses lossless compression that handles large areas of uniform colour extremely well, while lossy WebP spends bits describing edges it cannot represent cleanly. For logos, icons and screenshots, keep the PNG.
Does converting lose quality?
Yes. This is lossy re-encoding. The image is decoded and re-compressed, so detail is discarded. Converting an already-compressed JPEG is doubly lossy, because the first encoder’s artefacts get treated as real detail by the second.
Is transparency preserved?
Yes. WebP supports an alpha channel, so a transparent PNG stays transparent. That is its main advantage over JPEG, which has no alpha and renders transparency as black unless it is composited first.
Do all browsers support WebP now?
Every current browser does, including Safari since version 14 in 2020. The remaining consideration is older software, some desktop image editors and email clients still do not open WebP files.