PNG to WebP
Make PNGs smaller for a website by converting them to WebP, keeping transparent backgrounds. Every file stays on your device.
Drop PNG images here
Or any JPG, PNG, WebP, AVIF, SVG or HEIC, as many as you like. They become WebP files.
Your images are converted on this device and never uploaded. Location and other EXIF data are removed.
How this works: Method, 7 sources, Checked against 1 worked example,
How this works
Method
Each image is decoded by the browser itself (HEIC only where it opens HEIC, as Safari 17 and later does; the site ships no HEIC decoder, as HEVC is patented), turned upright, resized if asked and drawn on a canvas in a background worker, then written as JPG, PNG or WebP (libwebp where the browser can’t). The new file has no EXIF unless you keep it, GPS removed unless you keep all. SVGs are drawn through an image element, which runs no scripts and loads nothing they link to; JFIF files, already JPEGs, are copied byte for byte into a .jpg.
Sources
- RFC 9649: WebP Image Format (2024)
- Google for Developers: An image format for the Web (WebP)
- ISO/IEC 23008-12, Image File Format (HEIF) (Edition 2, 2022)
- AV1 Image File Format (AVIF), Alliance for Open Media (1.1.0, 2022)
- W3C: Portable Network Graphics (PNG) Specification (Third Edition, 2025)
- ITU-T T.81 | ISO/IEC 10918-1: JPEG (digital compression of continuous-tone still images) (1992)
- CIPA DC-008, Exif 3.0 (Exchangeable image file format)
How it’s tested
One worked example for this page is checked by automated tests before every release: given the inputs, the tool must show the expected answer.
Privacy
On your device. Nothing you enter or open leaves this browser. About privacy labels
Changes
- Added SVG to PNG (any size, transparent or coloured background, nothing the SVG links to is loaded) and JFIF to JPG (renamed without re-encoding).
- Browsers that can’t open HEIC say so before any file is chosen, with the quickest ways for the device and a QR code to carry on in Safari on an iPhone.
- HEIC now opens only where the browser reads it (Safari 17+), with tips elsewhere; the bundled HEIC decoder was removed because HEVC is covered by patents.
- First version: HEIC, WebP, AVIF, PNG, JPG, GIF and BMP to JPG, PNG or WebP, in batches with a ZIP, metadata removed by default, and nine conversion pages.
Why WebP for your site’s PNGs
PNGs are often the heaviest files on a web page. WebP keeps the transparency PNG is chosen for, but stores the picture in a fraction of the space, which shortens load times, especially on phones.
The quality slider sets lossy WebP compression. At 80 to 90, illustrations and photos with cut-out backgrounds look the same as the PNG, and the file is typically much smaller; flat graphics with few colours may save less. The list shows each file’s exact size before and after, so you can try a setting and judge.
Every current browser displays WebP. If you need the image elsewhere too, for email or print, keep the PNG as well; some desktop programs still don’t open WebP.
Safari can display WebP but can’t write it from a canvas, so in Safari the page loads a small WebP encoder (libwebp, about 115 KB) the first time you convert. Other browsers use their own encoder.
Good to know
- WebP stores an alpha channel with lossy images too, so transparent PNGs can become lossy WebPs. Source: RFC 9649: WebP Image Format
- Google’s comparison found lossless WebP about 26% smaller than PNG; lossy WebP saves more. Source: Google for Developers: An image format for the Web (WebP)
Open-source code inside, loaded only when needed: JPEGs are encoded with MozJPEG, PNGs packed with OxiPNG and WebP written with libwebp where the browser can’t. Pictures, HEIC included, are decoded by the browser itself. Licences and source
How to convert PNG to WebP3 steps, all on your device
- Add the PNGs. Drop the images for your site here: illustrations, icons, screenshots or product cut-outs.
- Choose the quality. Quality sets lossy WebP compression: 80 to 90 looks like the original in far less space. Transparency is kept either way.
- Download. Each file shows its new size and the saving. Save them singly or as a ZIP to upload to your site.
Frequently Asked Questions
Does PNG to WebP keep transparency?
Yes. WebP stores an alpha channel in both its lossy and lossless forms, so see-through areas and soft edges are kept.
Is the WebP lossless?
No; this converter writes lossy WebP with the quality you choose, because that is where the big savings are. At 90 the difference from the PNG is very hard to see.
Do all browsers show WebP?
All current ones do: Chrome, Edge, Firefox, Opera and Safari (on macOS from Safari 14 with macOS Big Sur).