An AVIF file is an image in the AV1 Image File Format. It is an open format from the Alliance for Open Media, and its files are often about half the size of a JPEG with the same quality. All current browsers show AVIF, but some apps cannot open it yet. To use it anywhere, convert it to JPG or PNG.
This guide explains what AVIF is, why websites save images as AVIF, how to open an AVIF file, and how to convert it. The main facts come from the Alliance for Open Media, MDN, and caniuse.com, checked in October 2026.
What is an AVIF file?
AVIF stands for AV1 Image File Format. It uses the compression of AV1, a video format, and stores the image in a HEIF container. HEIF is also the container of the HEIC photos from an iPhone. HEIC compresses the image with HEVC, and AVIF compresses it with AV1.
An AVIF file can hold:
- Lossy or lossless images. Lossy files are small, and lossless files keep every pixel.
- Transparency, like a PNG.
- HDR and wide color, for photos with bright highlights and rich color.
- Animation, like a GIF.
The main reason to use AVIF is the file size. The Alliance for Open Media says AVIF saves over 50% compared to JPEG and over 30% compared to WebP. MDN gives the same number: a lossy AVIF is around 50% smaller than a JPEG of similar quality. Smaller images make web pages load faster.
AVIF has two weak points. Older apps cannot open it. And a browser cannot show an AVIF until the full file has downloaded, because AVIF has no progressive loading, which JPEG has.
Why are images saving as AVIF?
You saved an image from a website, and you got a .avif file. The site did that on purpose.
Each time your browser asks a site for an image, it says which formats it can show. A browser that shows AVIF puts image/avif in that request. Many sites and image CDNs then send the AVIF version, because it is smaller. When you save the image, you save the file that the site sent.
So the same image can save as a JPG on one computer and as an AVIF on another. You cannot change the format with “Save image as”. Convert the file after you save it.
How to open an AVIF file
| Where | Opens AVIF |
|---|---|
| Chrome | Version 85 and later |
| Edge | Version 121 and later |
| Firefox | Version 93 and later |
| Safari on a Mac | Version 16.4 and later |
| iPhone and iPad | iOS 16 and later |
| Android | Android 12 and later |
| Mac apps (Preview, Photos) | macOS 13 Ventura and later |
| GIMP | Version 2.10.22 and later |
| Windows Photos | Not always. See below. |
About 96% of the people on the web use a browser that shows AVIF, so a browser is the easy way to view one. Drag the file into a browser window, or open it with Chrome, Edge, Firefox, or Safari.
On Windows, the Photos app can ask you to install the AV1 Video Extension from the Microsoft Store. If the file still does not open, open the file in a browser, or convert it to JPG.
How to convert AVIF to JPG or PNG
The free image converter converts AVIF in your browser. Your images do not leave your device, and you can convert many files at once.
- Open the image converter.
- Choose JPEG or PNG in the format list. Do this first: the converter uses the format that is selected when you add a file.
- Add your AVIF files. Choose files or a folder, or drop them on the page.
- Download each file, or download all of them as one ZIP.
The converter saves JPEG files at quality 82. It can also save WebP and TIFF.
JPG or PNG? Choose JPG for photos: the files are small, and every app opens them. Choose PNG when the image has a transparent background, or when it has sharp text or lines. A PNG of a photo is often several times bigger than the JPG.
AVIF vs WebP vs JPG vs PNG
| AVIF | WebP | JPG | PNG | |
|---|---|---|---|---|
| Photo file size | Smallest | Small | Medium | Large |
| Transparency | Yes | Yes | No | Yes |
| Animation | Yes | Yes | No | APNG only |
| Browser support | 96% | 97% | All | All |
For a website, AVIF gives the smallest files, and WebP is close. For a file that you send to other people, JPG and PNG are still the safe choice, because every app and every device opens them. Use JPG for photos, and PNG for logos, screenshots, and images with a transparent background.
For developers: serve AVIF with a fallback
About 4% of people use a browser that cannot show AVIF, so MDN recommends a fallback. The <picture> element lets the browser take the first format that it can show:
<picture>
<source srcset="/images/lake.avif" type="image/avif" />
<source srcset="/images/lake.webp" type="image/webp" />
<img src="/images/lake.jpg" alt="A mountain lake at sunrise" width="1200" height="800" />
</picture>A browser with AVIF loads lake.avif. Other browsers load the WebP or the JPG. The <img> tag keeps the alt text and the size for all of them.
Many image CDNs do this for you: they read image/avif in the request and send AVIF only to browsers that can show it. That is also why your saved images turn into AVIF files.
If your app makes its own images, such as social cards, product banners, or certificates, Bannerify renders each template to PNG, JPEG, or WebP, and you choose the format in each API request. A separate endpoint makes PDFs. Generate images shows the request. For social cards, the OG image guide has the sizes and the meta tags.
Try it
Convert your AVIF files to JPG or PNG with the free image converter. It needs no account and has no limit, because your own computer does the work.
To make images from templates with your own data, try the image generation API. The free plan includes 100 generations a month, and pricing has the other plans.
