What JPG to WebP does
WebP is the image format browsers prefer: at the same visual quality it produces files 25–35% smaller than JPG, and every current browser supports it. This converter re-encodes a JPG as WebP at the quality you choose, in your browser, without uploading the file. It is the standard step for anyone preparing photos for a website where page weight affects load time, search ranking and bandwidth costs.
Why WebP is smaller
JPEG dates from 1992 and compresses each 8×8 block independently. WebP, derived from the VP8 video codec, predicts blocks from their neighbours and only stores the difference, uses a better entropy coder, and applies a deblocking filter that hides compression seams. The result is less data for the same appearance — or better appearance for the same data.
| Quality | JPG size (typical photo) | WebP size | Saving |
|---|---|---|---|
| 90 | 100% | ≈ 70% | 30% |
| 80 | 100% | ≈ 68% | 32% |
| 70 | 100% | ≈ 65% | 35% |
| Lossless | n/a | ≈ 75% of PNG | 26% vs PNG |
Choosing the quality
- 0.8 — the usual web setting; visually identical to the source at normal size.
- 0.9 (default) — for images that will be zoomed, edited again or shown large.
- 0.6–0.7 — thumbnails, backgrounds and anything shown small.
- Because the source JPG is already lossy, this is a second generation of compression; keep quality at or above the JPG's own to avoid stacking artefacts.
Where WebP works — and where it does not
| Environment | Support |
|---|---|
| Chrome, Firefox, Safari, Edge, Opera (current) | Full |
| iOS 14+ / Android 4.2+ | Full |
| Windows 10/11 Photos app, Paint (Win 11) | Yes |
| macOS Big Sur+ Preview and Photos | Yes |
| Photoshop 23.2+, GIMP, Affinity | Yes |
| Older Office versions, many email clients | Often no |
| Digital photo frames, print kiosks, some upload forms | Usually no |
For the web, serve WebP with a JPG fallback using the <picture> element or let your CDN negotiate formats. For files you send to people or upload to services, check that the destination accepts WebP; if not, keep JPG.
Serving both formats
The standard pattern lets the browser pick the best format it supports:
| Approach | How |
|---|---|
| <picture> element | <picture><source srcset="photo.webp" type="image/webp"><img src="photo.jpg" alt="…"></picture> |
| CDN / image service | Cloudflare, Cloudinary, imgix and similar convert on the fly based on the Accept header |
| Build step | Static-site tools generate WebP alongside JPG automatically |
In 2026, with WebP support universal in browsers, many sites simply serve WebP directly and keep JPG only for download links.