The headline numbers
| JPG | WebP | |
|---|---|---|
| Introduced | 1992 | 2010 (Google) |
| Size at equal visual quality | Baseline | 25–35% smaller |
| Transparency | No | Yes |
| Animation | No | Yes (replaces GIF) |
| Lossless mode | No | Yes (smaller than PNG) |
| Browser support | Universal, forever | All major browsers since 2020 (Safari 14) |
| Non-browser software | Everything ever made | Modern apps; gaps in legacy tools |
WebP achieves the size win with techniques JPG's 1992 design predates: predictive block coding borrowed from video compression, better entropy coding, and smarter handling of flat areas. Same visible image, fewer bytes.
Where WebP is simply better
Websites — no contest. Every byte of image weight affects load time and Core Web Vitals, and WebP cuts image bytes by a quarter to a third across an entire site for free. It also collapses the old two-format workflow: instead of JPG for photos plus PNG for transparency, WebP covers both. This is why virtually every large site serves WebP (or its successor AVIF) today.
Screenshots and UI images also favor WebP: near-PNG sharpness on text at JPG-like sizes.
Where JPG still wins
- Maximum compatibility uploads — government portals, old CMSs, job boards, print shops. JPG has never been rejected by anything.
- Email attachments — some desktop email clients still preview JPG more reliably.
- Photography deliverables — clients open JPG in whatever decade-old software they own; labs print from it.
- og:image / social preview tags — scrapers are more predictable with JPG.
Converting is a two-second job
Both directions are one drop away, processed on your device: JPG → WebP to lighten a website, or WebP → JPG when an upload form refuses the modern format. If you're choosing formats for a whole site, the wider decision tree lives in Best image format for websites.