Convert PNG images to WEBP in your browser — private, instant, free.
WebP is a modern image format developed by Google that compresses better than both PNG and JPG while supporting everything PNG does — including full alpha transparency. For PNG source images it typically produces files 25-35% smaller in lossless mode, and dramatically smaller if you allow lossy compression.
This is one of the few format conversions with essentially no downside for web use, which is why it has become standard practice.
WebP offers both modes, which is what makes it more flexible than PNG or JPG individually.
| Mode | Quality | Typical size vs PNG | Best for |
|---|---|---|---|
| Lossless WebP | Pixel-identical | 65-75% | Logos, screenshots, line art |
| Lossy WebP (q90) | No visible difference | 15-25% | Photographs, complex images |
| Lossy WebP (q75) | Slight softening | 8-15% | Web photos where size matters |
Crucially, lossy WebP still supports transparency. That combination does not exist in the older formats — JPG gives you lossy but no alpha, PNG gives you alpha but only lossless. A transparent product image that had to be a 2 MB PNG can become a 200 KB lossy WebP with the transparency intact.
WebP is supported by every current browser — Chrome, Firefox, Edge, Safari and all major mobile browsers. Safari was the last holdout and added support in 2020 with version 14. In practice, support now exceeds 97% of global traffic.
The remaining concerns are not browsers but other software: some older desktop applications, email clients and content management systems still do not handle WebP. If an image needs to be opened by arbitrary third-party software rather than displayed on a web page, PNG remains the safer choice.
If you need to support very old browsers, the picture element lets the browser choose:
Browsers that understand WebP take the first source; the rest fall back to the PNG. The img tag remains required — it provides the alt text and the actual fallback.
Images are usually the largest component of page weight, so this conversion has a direct and measurable effect. Cutting image bytes by a third improves Largest Contentful Paint, which is one of Google's Core Web Vitals and a ranking signal. On image-heavy pages the difference is often the single largest performance win available, ahead of anything you can do to scripts or stylesheets.
Two further things worth doing at the same time: resize images to the largest size they will actually be displayed at, since serving a 4000px image into a 800px slot wastes most of the bytes regardless of format, and add loading="lazy" to images below the fold.
Alpha transparency converts faithfully, including partial transparency and soft edges. Animation is supported by WebP, though animated PNG conversion is not handled here. Most metadata is dropped in conversion, which is usually desirable for web images — it removes camera details and any location data — but worth knowing if you rely on embedded copyright information.
Encoding happens in your browser through the Canvas API, which has native WebP support. Nothing is uploaded, so there is no file size cap imposed by a server and your images stay on your device throughout.
Yes, including partial transparency and soft edges, and in both lossless and lossy modes. That combination is WebP's main advantage — JPG offers lossy compression without alpha, PNG offers alpha without lossy compression.
All current ones do, including Safari since version 14 in 2020. Support covers over 97% of global traffic. Use a picture element with a PNG fallback if you need to cover the remainder.
Lossless WebP is typically 25-35% smaller than the equivalent PNG. Lossy WebP at high quality is often 75-85% smaller, which is why it is worth considering even for images that need transparency.
For images displayed on web pages, yes. For images that need to be opened in arbitrary desktop software, attached to emails or uploaded to systems with older format handling, PNG is still the safer choice.
Not in lossless mode, which reproduces the PNG pixel for pixel. Lossy mode discards some detail in exchange for a much smaller file — at quality 90 the difference is not visible at normal viewing sizes.