ConvertPixel · WEB APP

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Convert JPEG to AVIF

Drop a JPEG file below and get a AVIF back. The conversion happens on your own machine, so nothing is uploaded and there is no size or quantity limit beyond what your browser can hold in memory.

Drop images here

Ctrl/⌘ VPaste a screenshot or copied image

Accepts JPEG

Lower means a smaller file. 75 is a good default for photos.

    100% in your browser Files are never uploaded.

    Why convert JPEG to AVIF?

    For the same picture, AVIF usually lands well under the size of the JPEG original. That matters when you are trimming page weight or squeezing under an upload limit.

    AVIF supports an alpha channel, so you can cut out a background after converting. The conversion itself will not invent transparency that the JPEG file never had.

    Both formats are lossy. Every re-encode discards a little more detail, so it is worth starting from the original rather than from a copy that has already been through this a few times.

    This is the aggressive end of web image optimisation. AVIF will typically halve a JPEG at matching visual quality — a bigger saving than WebP offers, and on an image-heavy page that shows up directly in loading time. The trade-offs are real but narrow, and worth knowing before you re-encode a whole library.

    Before you convert

    Encoding is slow, and that is the format working

    AVIF is built on AV1, a video codec that searches hard for redundancy. That search is where the compression comes from, and it costs time — a single large image can take several seconds in the browser, where JPEG takes milliseconds. For a batch this adds up. It is a one-time cost paid at build time in exchange for bytes saved on every single page view, which is usually a trade worth making.

    Second-generation encoding applies here too

    The JPEG already discarded detail, and AVIF now compresses what is left, artefacts included. Encoding from the original camera file or master export gives a smaller and cleaner AVIF than routing through the JPEG. And as with WebP, resist raising quality to compensate — high settings make AVIF spend bytes faithfully reproducing JPEG blocking, which is the last thing you want to preserve.

    Keep a fallback for a while longer

    Browser support is good — all current major browsers read AVIF — but it arrived years after WebP and the long tail of older devices, in-app browsers and email clients is correspondingly longer. Serve it through a picture element with a JPEG or WebP fallback and the question stops mattering.

    What carries over

    • Pixel dimensions
    • Visual appearance at sensible settings
    • Roughly half the file size

    What does not

    • A little more detail — a second lossy pass
    • Fast encoding
    • Support on older devices and in email

    JPEG vs AVIF at a glance

    PropertyJPEGAVIF
    CompressionLossyLossy
    TransparencyNoYes
    Typical file size100% of an equivalent JPEG40-55% of an equivalent JPEG
    CompatibilityOpens everywhere, including decades-old softwareAll current browsers; some older desktop apps lag behind
    Usually comes fromDigital cameras and photo sharingWebsites optimising page weight

    Frequently asked questions

    Are my JPEG files uploaded anywhere?

    No. The decoder and encoder are WebAssembly modules that run inside this page. The network tab may show a codec downloading the first time you use a format, but no request contains your file. On supported browsers, a codec that has already been used is cached so the same conversion can work offline.

    Is there a file size or quantity limit?

    There is no limit imposed by us. The practical ceiling is your device’s memory, since the image has to be held uncompressed while converting. On a typical laptop, images up to around 100 megapixels convert without trouble.

    Will converting to AVIF lose quality?

    AVIF is a lossy format, so some data is discarded. At the default quality setting the difference is not visible at normal viewing sizes. If you need an exact copy of the pixels, choose PNG instead.

    Does it work on a phone?

    Yes. The same WebAssembly modules run on mobile browsers. Conversion is slower than on a desktop because phone CPUs are weaker, and very large images are more likely to hit memory limits.

    Will converting from JPEG lose more quality?

    A little, if the target is also lossy. The JPEG you start with has already discarded data, and a second lossy encode discards a bit more. At quality 80 or above that second loss is hard to spot, but it is exactly why you should keep the original rather than converting the same file back and forth.

    Where does AVIF actually work?

    Every major browser decodes AVIF natively, so it is safe for use on the web. Desktop applications lag further behind — plenty of image viewers and editors still cannot open it. Encoding is also noticeably slower than the other formats here, so expect a large image to take a few seconds.

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