Why WebP is smaller
WebP borrows its compression from the VP8 video codec. Where JPEG compresses each 8×8 block largely on its own, WebP predicts each block from its already-encoded neighbours and stores only the difference — so smooth areas such as skies and skin cost very little.
It also uses a more efficient entropy coder and supports an alpha channel, which JPEG lacks entirely.
Browser support is no longer a concern
Every current browser supports WebP: Chrome and Opera since 2010, Firefox and Edge since 2018–19, Safari since version 14 in 2020. Coverage is above 95% of global traffic.
The remaining caveat is not browsers but upload forms. Many government portals, job sites and older CMS installations still reject WebP, so use JPEG for submissions and WebP for anything you host yourself.
WebP and Core Web Vitals
Largest Contentful Paint is usually determined by an image, and it is one of the three Core Web Vitals Google uses as a ranking signal. Cutting your hero image by 30% cuts directly into LCP.
Pair the format change with correct sizing. Serving a 3000px-wide WebP into a 1200px-wide column still wastes most of the bytes you just saved — resize the dimensions as well as converting the format.
Frequently asked questions
- Is WebP better than JPEG?
- For web delivery, yes — smaller at equal quality, with transparency support. For upload forms and maximum compatibility, JPEG is still the safer choice.
- Do all browsers support WebP?
- All current ones do, covering above 95% of traffic. Safari added support in version 14 (2020), which was the last significant gap.
- What quality setting should I use for WebP?
- Around 80–85 is the sweet spot for photographs — visually indistinguishable from the original at a fraction of the size. WebP holds up better than JPEG at low settings, so you can push further if you need to.