Convert PNG to WebP
WebP keeps the alpha channel that makes PNG useful while compressing far harder, so transparent logos, icons and screenshots usually end up a fraction of the size. Drop your PNGs, pick a quality, and download WebP files for your site or app. Nothing is uploaded.
How to use the PNG to WebP
- Add the PNGs — UI screenshots, transparent logos, illustrations, icons.
- Set quality. Graphics with hard edges want 90 or higher; photographs saved as PNG are fine around 82.
- Convert and read the size summary to see the saving.
- Download the results, individually or as one ZIP.
The best saving of any common conversion
PNG compresses losslessly with DEFLATE, the same algorithm as ZIP. That is efficient for large blocks of identical colour but it can never approach what a modern image codec achieves, because it is not allowed to change a single pixel. WebP is allowed to, and the difference is dramatic: a 1.4 MB PNG screenshot commonly becomes 120–200 KB, and a transparent product cut-out often drops by 70% or more. Unlike PNG to JPG, you do not have to give up transparency to get there.
Transparency, properly handled
WebP supports the same 8-bit alpha channel as PNG, so feathered edges, soft shadows and anti-aliased type stay smooth. There is no matte colour and no halo. This is the main reason to prefer WebP over JPG for logos and interface assets.
Lossy, not lossless
The encoder built into browsers writes lossy WebP. At quality 90–100 the result is visually indistinguishable from the PNG for almost any content, but it is not a bit-exact copy: if you zoom to 400% on an area of flat colour beside a hard edge you may find pixels that differ by one or two levels. For most work that is irrelevant. It matters if the image is going to be compared programmatically, used as a texture atlas, or if it is a diagram where absolute pixel fidelity is part of the point — in those cases keep the PNG.
Typical results
| Source PNG | Quality | Result |
|---|---|---|
| 1920 × 1080 app screenshot, 1.4 MB | 90 | ≈ 150 KB |
| 512 × 512 transparent logo, 90 KB | 95 | ≈ 20 KB |
| Photograph saved as PNG, 6 MB | 82 | ≈ 250 KB |
Practical notes
Serve WebP with a PNG fallback if you support very old browsers, using a <picture> element. Keep the PNG masters — you can always regenerate WebP from a PNG, but you cannot recover PNG-grade pixels from a lossy WebP. Metadata such as text chunks and colour profiles is not copied into the WebP; the output is sRGB pixels only.
Frequently asked questions
Is transparency kept?
Yes. WebP has a full 8-bit alpha channel, so transparent and semi-transparent pixels come across unchanged.
How much smaller are the files?
Screenshots and interface graphics typically drop by 70–90%; photographs saved as PNG can drop by 95%. Small flat icons save least in absolute terms.
Is this a lossless conversion?
No — browsers only expose the lossy WebP encoder. At quality 90 and above the difference is invisible, but keep your PNG masters if you need exact pixels.
Will WebP work in email?
Support is unreliable in desktop mail clients. Use PNG or JPG for email and WebP on the web.
Privacy
This tool runs entirely inside your browser using WebAssembly and the Canvas/File APIs. Your files are never uploaded to ToolFlint or any third party; you can verify this in your browser's network tab or by switching to airplane mode after the page loads. Read how we process files.
Last updated 2026-09-23.