Add up to 30 iPhone HEIC photos (up to 50 MB each) and convert them to AVIF with libavif at the quality you choose (10 to 100, default 85). The tool decodes HEIC itself, so it works in any current browser, and the encoding happens on your device without uploads. AVIF encoding is slower than JPG or WebP, so large batches take a little while.
Convert HEIC photos to AVIF for small files
AVIF is an image format based on the AV1 video codec, and it usually produces the smallest files of the formats browsers support. Converting HEIC photos to AVIF typically gives files smaller than WebP and much smaller than JPG at similar visual quality.
Why AVIF files are small
AVIF uses the intra-frame coding tools of AV1, which are more advanced than the VP8 coding behind WebP or the block-based DCT compression of JPG. On a site with many photos, that adds up to less bandwidth and faster pages.
Browser support
Current versions of Chrome, Firefox, Safari (16.4 and later) and Edge all display AVIF. Some older browsers and many desktop programs don't, so on websites it's common to offer a WebP or JPG fallback with the <picture> element.
When to choose AVIF over WebP or JPG
Choose AVIF when the smallest file matters most: modern websites, image-heavy pages, and apps where bandwidth costs money. Choose WebP when you need wider support in older software, and JPG when the photos go to email, documents or anyone with an older device.
Private processing
Your HEIC photos are converted in your browser and never uploaded. The AVIF files are saved without the original EXIF data, which removes the GPS location too. The HEIC decoder, libheif, is listed with its license on the open source licenses page.
Frequently Asked Questions
Is AVIF better than HEIC?
For the web, yes: AVIF compresses about as well as HEIC or better, and current browsers display it, while only Safari shows HEIC. HEIC stays the iPhone's native capture format, so converting is an extra step that pays off when the photos are published online.
Why are my AVIF files taking longer to convert?
AV1 encoding takes much more computation than JPG or WebP, because the encoder searches many ways to compress each part of the image. The time depends on your device and the photo size, and it's spent once for files that are smaller on every later download.
Does AVIF support transparency?
Yes. AVIF has an alpha channel, so any transparency in the HEIC is kept in the AVIF output. Regular iPhone camera photos have no transparent areas.
Is AVIF widely supported enough for production use?
Yes, with a fallback. All current major browsers support AVIF, so most visitors get the smaller file, and a WebP or JPG fallback in a <picture> element covers older browsers.