Convert JPG to WebP
Convert JPG to WebP online, free and 100% in your browser. No upload, no signup, no size limit — WebAssembly does the work on your device.
How to convert an image
- Drop or pick your JPG file — or paste it with Ctrl/⌘+V.
- WebP is already selected as the target; tune the quality slider if you like (default 80).
- Convert, compare the before/after, and download — all on your device.
Why convert to this format?
JPEG is the universal lossy photo format — small and readable everywhere, but with no transparency. WebP is a modern web format that is typically 25–35% smaller than JPG or PNG at the same quality, with transparency.
OptImg runs the same Rust codecs desktop tools use, compiled to WebAssembly, so you get desktop-grade WebP output at a sensible default (quality 80) — adjustable at any time — without ever uploading your image.
Everything happens locally: your JPG is decoded, re-encoded to WebP and handed straight back as a download. No server sees a single byte, which is why there's no queue and no file-size cap.
Frequently asked questions
- Is my JPG uploaded to a server?
- No. The JPG-to-WebP conversion runs entirely in your browser with WebAssembly — your file never leaves your device, there is no queue, and no size limit beyond your device's memory.
- Will converting JPG to WebP lose quality?
- WebP is lossy, tuned to a visually transparent default (quality 80) that you can raise or lower with the slider. If the conversion can't produce a smaller file than your original, we hand the original back instead.
- Is the JPG to WebP converter free?
- Yes — completely free, with no signup, no watermark and no cap on how many files you convert. There is nothing to install; it runs in your browser.