PNG to WebP converter

Convert PNG files to WebP inside this page. No upload, no limit on how many, no watermark.

  • 0 uploads
  • No limits
  • No signup
  • Works offline

PNG and WebP, side by side

PNGWebP
Released19962010
Compressionlosslessboth
Transparencyyesyes
Animationnoyes
Supporteverywhere, without exceptionall current browsers; patchy outside them

What actually changes

For screenshots and interface graphics, lossless WebP typically comes out 20–30% smaller than PNG with identical pixels. For photographs saved as PNG, switching to lossy WebP can cut the size by 90% with no visible change.

PNG is a lossless format built around DEFLATE compression and a full alpha channel, released in 1996. Its real strength is that pixel-exact reproduction and true transparency, which makes it right for screenshots, logos and line art. The reason you are on this page is almost certainly the other side of that coin: file sizes several times larger than a lossy format when the content is photographic.

WebP arrived in 2010 and is Google's replacement for both JPEG and PNG, derived from the VP8 video codec. It gives you roughly 25–35% smaller than JPEG at matching visual quality, with transparency and animation in the same container. The trade-off worth knowing about before you commit: still refused by some desktop applications, older phones and a surprising number of official upload forms.

How the conversion works here

Your file is decoded in a Web Worker inside this browser tab — by the browser's own image pipeline where it can, and by a WebAssembly build of libheif or libavif where it cannot. The decoded pixels are then re-encoded with Google's libwebp, the same encoder Squoosh uses.

All of that happens on the processor in front of you. There is no upload step, no queue and no server, which is why there is no size cap, no daily allowance and no paid tier — and why the whole thing keeps working with the network switched off.

Doing more than one thing

Most people converting a format also need it smaller or a different size. The result screen hands your converted files straight to the compressor or the resizer in one click — no second download, no re-selecting files. If you need several formats, the general converter lets you pick the output each time.

How it works

  1. 01Add your PNG filesDrop them on the page, click to browse, paste from the clipboard, or drop a whole folder.
  2. 02Conversion runs on your deviceEach file is decoded and re-encoded as WebP by a WebAssembly codec in a background thread. Nothing is uploaded.
  3. 03Adjust if you need toMove the quality slider — 90 is visually indistinguishable from the source for most photographs.
  4. 04DownloadSave one file, or take the whole batch as a zip built on your device.

Questions people actually ask

Why convert PNG to WebP?
PNG is a lossless format built around DEFLATE compression and a full alpha channel. Its weakness is that file sizes several times larger than a lossy format when the content is photographic. WebP gives you roughly 25–35% smaller than JPEG at matching visual quality, with transparency and animation in the same container, which is usually the reason people make this exact conversion.
Will I lose quality?
A little, unavoidably. PNG and WebP are both lossy, so this is a re-encode. At quality 90 the difference is invisible at normal viewing size; drop below about 75 and it starts to show in skin tones and gradients.
Is there a file size or batch limit?
No. Nothing is uploaded, so there is no bandwidth to pay for and nothing to ration. The only ceiling is your own device’s memory.
Are my files uploaded?
No. Open your browser’s developer tools, watch the Network tab, and convert something — no request carries your file. The counter in the page header measures the same thing continuously.
Where is WebP supported?
All current browsers; patchy outside them. WebP arrived in 2010, and still refused by some desktop applications, older phones and a surprising number of official upload forms.