What is a JPG file?
JPEG has been the default format for photographs since 1992. It uses lossy compression tuned for natural images, which lets it shrink photos to a fraction of their raw size while keeping them visually convincing. Virtually every camera, phone, browser, and app on the planet can open a JPG.
In short, JPG is the universal standard for photographs. It is best for photographs, screenshots of photos, email attachments, and anywhere maximum compatibility matters more than perfect fidelity. Its main limitations are no transparency support, visible artifacts at low quality settings, and quality degrades each time the file is re-saved.
Why convert JPG to AVIF?
AVIF is built on the AV1 video codec and delivers the strongest compression of any mainstream image format — files are often about half the size of an equivalent JPG and noticeably smaller than WebP at the same visual quality. It supports transparency, HDR, and wide color gamuts.
Converting from JPG to AVIF makes sense when you need performance-critical websites where every kilobyte counts, and modern image pipelines that can serve fallbacks. AVIF is supported by all current versions of Chrome, Firefox, Safari, and Edge.
AVIF supports full transparency, so images you later edit can take advantage of an alpha channel — though a converted JPG starts out fully opaque.
How to convert JPG to AVIF
Drag and drop one or more JPG files into the box above (or click to browse). Adjust the quality slider if you want smaller files or higher fidelity, then press Convert. Each file is decoded and re-encoded as AVIF on your own device in a second or two, and you can download results individually or grab everything as a ZIP.
Unlike most online converters, FileLark never uploads your files to a server. The conversion runs entirely inside your browser using modern web technology, which means it works offline once the page has loaded, there are no file size queues or daily upload limits, and your images can never be stored, scanned, or leaked — they simply never leave your device.