Free converter · nothing uploaded
Convert PNG to WebP
Convert a PNG to WebP to make it smaller while keeping transparency — a good trade for the web. There’s a catch worth knowing for screenshots, which we’ll be straight about. It all runs in your browser; nothing is uploaded.
Your images never leave this device, and every file is built in your browser.
Drop your PNG images here
or
PNG in, WebP out. As many as you like, converted on your device
80% is a good balance of size and clarity.
Loading the in-browser HEIC decoder (one time, ~1.5 MB)…
Why convert PNG to WebP?
For a photographic or richly-coloured PNG, WebP is a clear win: smaller than PNG, and unlike JPG it keeps the alpha channel, so transparent logos and UI assets stay transparent.
The catch: a browser can only make lossy WebP. For a flat screenshot or diagram, a lossless PNG (especially a palette PNG) can be both sharper and smaller than lossy WebP — so WebP isn’t automatically the right call.
What you gain
- Smaller than PNG for photos and rich images
- Keeps transparency, unlike JPG
- Modern, well supported on the web
What you lose or trade
- Browser WebP is lossy — flat screenshots can soften
- Not ideal where a lossless/indexed PNG would be smaller AND sharper
- Compatibility gaps in some older software
The honest recommendation
For a photo-like PNG, WebP wins; for a flat screenshot, a lossless PNG can be both smaller and sharper than this lossy WebP — check with our format advisor first.
Measure it on your own image with the format advisor →PNG to WebP: questions
Does WebP keep transparency from a PNG?
Yes — WebP supports an alpha channel, so transparent areas are preserved (this is its advantage over JPG for logos and UI assets).
Is this lossless WebP?
No. A browser can only produce lossy WebP from a canvas. For a flat, few-colour image a lossless PNG is often both smaller and sharper — our format advisor measures it so you can compare.
Will a screenshot look worse as WebP?
It can soften slightly, because the WebP here is lossy and screenshots have hard edges. For screenshots, compare against keeping the PNG — sometimes the PNG is the better answer.
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