PNG is the safe default for screenshots, logos and anything with a transparent background, but it is also one of the heaviest image formats on the web. WebP keeps the transparency and the sharp edges while usually cutting the file size by more than half. This converter turns one or many PNG files into WebP without sending them anywhere: the decoding and encoding happen inside your browser.
Drop your PNGs, choose a quality level, press Convert and download each file or everything as a ZIP. The size before and after is shown for every image so you can judge whether the saving is worth it.
What is a PNG to WebP converter?
A PNG to WebP converter re-encodes the pixels of a PNG image using Google's WebP codec. PNG stores every pixel losslessly, which is why a 1920 by 1080 screenshot can weigh several megabytes. WebP offers both lossy and lossless modes; the lossy mode used here discards detail the eye cannot see, much like JPG, but with better compression and full support for an alpha channel.
Because the browser's own image decoder does the work, the conversion is as fast as opening the image. Nothing is uploaded, so there is no queue, no file limit from a server and no copy of your image left behind.
When to convert PNG to WebP
Website images and page speed
Every modern browser renders WebP. Swapping PNG assets for WebP is one of the fastest ways to improve Largest Contentful Paint scores and to pass Core Web Vitals, especially for hero images and screenshots.
Transparent logos and icons
JPG cannot store transparency, so designers were stuck with PNG. WebP supports an alpha channel, which means a logo that weighs 300 KB as PNG often becomes 40 KB as WebP with the background still transparent.
Sharing many screenshots
Documentation, bug reports and app store listings involve dozens of screenshots. Converting the batch to WebP keeps the text crisp at quality 80 to 90 while the folder shrinks dramatically.
How the conversion works
The browser decodes the PNG into raw pixels with createImageBitmap, draws them on an off-screen canvas inside a Web Worker and asks the canvas to encode the result as image/webp at the quality you chose. Because the work happens in a worker, the page stays responsive while a batch is converting.
Quality 100 is close to lossless but produces larger files. For photos, 75 to 85 is a good range. For screenshots with text, 85 to 90 keeps letters sharp. Try two values on one file and compare the sizes shown in the results list.
Como usar esta ferramenta
- Drop one or more PNG files on the box above, or click it to browse.
- Move the quality slider. Lower values give smaller files.
- Press Convert and wait for each file to show Done.
- Download files one by one or press Download all to get a ZIP.
Limitations
- Animated PNG (APNG) is converted as a single still frame.
- The output is lossy WebP. A lossless WebP option is planned.
- Very large images (over 50 MB or above 16,000 pixels on a side) may exceed browser memory, especially on phones.
- Metadata such as text chunks inside the PNG is not carried over.