Why convert PNG to WebP
WebP makes web pages faster: the same picture is usually 25 to 35 % smaller than PNG and keeps transparency. It is the format to use for images on your own site or online store.
PNG is PNG, the lossless format of screenshots, logos and graphics with transparency; WebP is WebP, Google's web format that many sites now serve because it is small.
What changes
- WebP compresses with a small, normally invisible loss; at the default quality (92) the file is much smaller.
- Transparency is kept.
- Photo metadata such as camera details and GPS location is not copied to the new file.
Nothing is uploaded
Your pictures are converted by your own browser and saved straight back to your device. There is no sign-up, watermark or daily limit, and you can convert up to five files at once.
How this works
The picture is decoded by your browser in a Web Worker, with phone orientation applied, then encoded as WebP by the browser's own encoder (canvas convertToBlob) at the chosen quality. Up to five files are converted one after another, and several results can be downloaded together as a ZIP. Nothing is uploaded, so there's no account or daily limit.
Frequently asked
Will the picture lose quality?
At the default quality of 92 the difference is not visible; choose 85 or 75 for smaller files.
Are my images uploaded?
No. The conversion runs in your browser on this device; nothing is sent to a server.
Can I convert several files at once?
Yes, up to five at a time. Several results can be downloaded one by one or together as a ZIP.
Sources
- W3C — Portable Network Graphics (PNG) Specification (Third Edition)
- RFC 9649 — WebP Image Format
- HTML Standard — OffscreenCanvas convertToBlob()
Reviewed Oct 19, 2026 · test vectors fixtures/convert/image/png-to-webp/