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PNG to WebP Converter
This free PNG to WebP converter shrinks your PNG images into fast-loading WebP files right in your browser. Drop in a photo or screenshot, pick a quality level, and download a WebP that looks the same but takes up far less space. Your image never leaves your device: the whole conversion runs on your own computer, with no upload, no queue, and no sign-up.
All processing happens in your browser. Your image is never uploaded to any server. Converting a GIF instead? Our GIF to WebP converter handles GIF files (first frame only) — this page is for PNG images.
How it works
PNG and WebP store pictures in very different ways. PNG keeps every pixel exactly as it was, which is perfect for diagrams and logos but wasteful for photos: a detailed 1200 × 800 photo saved as PNG can easily reach several megabytes. WebP is a newer format built for the web. It studies the picture and throws away only the tiny details the eye cannot see, packing the same photo into a much smaller file. At quality 80, most photos look identical to the original while using a quarter of the space or less, which means web pages load faster and use less data.
The quality slider controls how much detail is kept. It runs from 50 to 100. Quality 80 is a good all-round choice for photos and screenshots: sharp to the eye and much smaller than the PNG. Quality 90 or above keeps fine detail for product photos or pictures you plan to zoom into, at the cost of a larger file. Quality 50 to 70 makes the smallest files, which suits thumbnails and background images where perfect detail does not matter. There is no single right setting — try 80 first, and only go higher if you can see a difference when you zoom in.
The resize option trims the picture's dimensions before converting, which shrinks the file even further. A photo that will only ever be shown 800 pixels wide does not need to be stored at 1920 pixels, so choosing "Max width 800 px" cuts the file down twice: fewer pixels, then WebP compression on top. The picture is only ever shrunk, never stretched — a small picture stays small, and its proportions are kept exactly, so nothing is squashed or stretched out of shape.
Before converting, the tool checks that your file really is a PNG by reading its first eight bytes and looking for the PNG signature, the marker every genuine PNG starts with. A JPEG or a text file renamed to end in .png fails that check and is rejected with a friendly message. Files that pass are drawn onto a canvas in your browser and encoded as WebP with the quality you chose, using the browser's own image encoder. Transparency is preserved, so a logo with a see-through background stays see-through. If a browser cannot encode WebP at all — very old browsers, for example — the tool says so plainly instead of handing you a broken file. Nothing is uploaded at any point, so the conversion works with no internet connection once the page has loaded.
The finished file is named from the file name box — by default image.webp — and downloads straight to your computer. WebP images work in all modern browsers, on phones and computers alike, and are accepted by most website builders, online shops, and social platforms. If a particular tool or printer refuses a WebP file, convert a copy back to PNG or JPG with one of the other converters on this site; keep the WebP for the web, where its small size earns its keep.
Worked example
A shop owner has a detailed product photo saved as photo.png, 1200 × 800 pixels and 2,884,862 bytes (about 2.75 MB). The photo is too heavy for her online shop page, which loads slowly on phones.
Step 1: She drops photo.png onto the converter. The tool checks the PNG signature, reads the picture, and shows a preview. The result line reads "photo.png ready — 1200 × 800 pixels".
Step 2: She keeps the default settings: quality 80, original size, file name "image".
Step 3: She presses Convert to WebP. The picture is encoded as WebP at quality 80.
Step 4: She presses Download .webp to save the file as image.webp.
The result is a WebP file of 658,292 bytes (about 643 KB) — 77% smaller than the 2.75 MB PNG — with the same 1200 × 800 size and no visible change in quality. Raising the quality to 90 instead would give a file of 803,320 bytes (about 785 KB), still 72% smaller than the original PNG.
FAQ
What is WebP, and why convert a PNG to it?
WebP is a modern image format that compresses photos far better than PNG, so the same picture takes up much less space and loads faster on a website. A PNG is best for keeping every pixel exactly, while a WebP at quality 80 to 90 looks the same to the eye at a fraction of the file size, which is why websites use WebP for photos and screenshots.
What quality setting should I choose?
Quality 80 is a good all-round choice: photos stay sharp and the file is much smaller than the PNG. Use 90 or above when fine detail matters, such as a product photo or a picture you plan to print. Use 50 to 70 only when the smallest possible file matters more than perfect detail, for example a thumbnail or a background image.
Does the WebP file keep the transparency of my PNG?
Yes. WebP supports transparency just like PNG, so see-through areas of your picture stay see-through in the converted file. A logo with a transparent background converts cleanly and can be placed over any background colour on a web page.
Why is my WebP file bigger than the PNG?
It can happen with very simple pictures. A flat-colour logo or a plain diagram compresses extremely well as a PNG, and converting it to WebP at quality 100 can produce a larger file. If that happens, lower the quality slider to 80, or keep the original PNG — WebP saves the most space on detailed photos and busy screenshots.
Are my images uploaded to a server?
No. Your PNG is decoded and re-encoded as WebP entirely in your browser, using JavaScript running on your own device. Nothing is uploaded, so photos, screenshots, and private images stay on your computer.