What is this JPEG to AVIF converter?
A free, browser-based tool that converts JPEG images to AVIF in batch. Upload one or many images, set a quality level, and download everything as a single ZIP — at the original resolution. All processing happens locally in your browser, so your images are never uploaded.
Shrinking JPG photo weight for Core Web Vitals
On most marketing and e-commerce pages, photos are the heaviest assets, and the hero image is frequently the Largest Contentful Paint element itself. Re-encoding JPG to AVIF typically cuts 30 to 50% of the bytes at similar visual quality, and that saving lands exactly where speed metrics are measured: faster LCP, lighter pages on mobile connections, more headroom in a performance budget.
Every modern browser renders AVIF, so for images served on your own site the switch is safe for current traffic. Product grids, blog covers, and gallery pages are the natural first candidates because the same saving repeats across dozens or hundreds of files.
Quality choices, and where the AVIF copies should not go
A JPG source is already lossy, so this is a re-encode: pick a mid-to-high quality setting and the added loss stays below what anyone notices at normal viewing sizes, while most of the size win is preserved. Chasing the minimum on flagship imagery is rarely worth the artifacts. Keep the original JPGs as masters.
The caveat is everything outside the browser. Many desktop applications, Office, older operating system viewers, and most CMS and marketplace upload forms still refuse AVIF. Convert the copies you serve on your site, and keep JPG for images that travel into decks, documents, email attachments, or third-party platforms.
How to use it
- Upload one or more JPEG images on the left (drag & drop or click).
- Adjust the quality slider to balance size and quality.
- Press “Convert & download zip” to get every image as AVIF.