AV1 Image File Format
AV1 Image File Format (.avif) – Complete Guide
The .avif file format has quickly become one of the most talked-about image formats on the modern web. Combining cutting-edge compression technology with broad color support, AVIF represents a significant leap forward from older formats like JPEG and PNG. This guide covers everything you need to know — from its origins and technical details to practical tips for opening, using, and converting AVIF files.
What is the AVIF Format?
AVIF, short for AV1 Image File Format, is a modern image file format based on the AV1 video codec. It stores still images and image sequences using the same compression technology developed for high-efficiency video streaming. The format uses the ISOBMFF (ISO Base Media File Format) container — the same container family used by MP4 video files — which allows it to store rich metadata, HDR content, and even animated sequences.
AVIF was developed by the Alliance for Open Media (AOMedia), a consortium that includes major technology companies such as Google, Apple, Microsoft, Mozilla, Netflix, and Amazon. The format was officially released in 2019 as a royalty-free, open standard. This royalty-free nature is one of the key reasons AVIF gained rapid adoption, particularly as an alternative to HEIC/HEIF, which carries licensing costs associated with the HEVC codec.
Since its release, AVIF support has grown substantially. Major web browsers including Chrome, Firefox, and Safari added native support between 2020 and 2022, and it is now widely used for web delivery of high-quality images with minimal file sizes.
Technical Specifications
Compression
AVIF uses AV1 intra-frame compression, which means it encodes images using the same perceptual compression algorithms found in AV1 video. It supports both lossy and lossless compression modes. In lossy mode, AVIF typically achieves file sizes 50% smaller than JPEG at equivalent visual quality. The format uses advanced techniques such as chroma subsampling, transform coding, and in-loop filters to remove redundant data while preserving visual fidelity.
Color Depth and Color Spaces
AVIF supports a wide range of color configurations, making it suitable for both standard and professional use cases:
- Color depth: 8-bit, 10-bit, and 12-bit per channel
- Color spaces: BT.601, BT.709, BT.2020, and sRGB
- HDR support: Full support for High Dynamic Range content via PQ (Perceptual Quantizer) and HLG (Hybrid Log-Gamma) transfer functions
- Wide color gamut (WCG): Supports Display P3 and Rec. 2020 color gamuts
- Chroma subsampling: 4:2:0, 4:2:2, and 4:4:4
- Transparency (alpha channel): Fully supported
Resolution and Animation
AVIF supports images up to 65,536 × 65,536 pixels in theory, though practical limits depend on the encoder. It also supports animated AVIF sequences, functioning similarly to animated GIF or WebP but with far superior compression and quality. Multi-layer images and image grids (for tiling large images) are also supported within the format specification.
Metadata
The format supports embedded Exif, XMP, and IPTC metadata, which is important for photographers and content management systems. ICC color profiles can also be embedded for accurate color reproduction across different displays.
Common Use Cases
- Web publishing: AVIF is increasingly used to serve product images, hero images, and thumbnails on websites, significantly reducing page load times.
- Photography: High bit-depth and wide color gamut support make it suitable for storing HDR and professionally graded photographs.
- Streaming platforms: Companies like Netflix have contributed heavily to the format's development, using it for thumbnail images and promotional artwork.
- Mobile applications: Its small file sizes make AVIF ideal for apps that need to display many images without consuming excessive storage or bandwidth.
- E-commerce: Online retailers benefit from faster-loading, high-quality product images that improve both user experience and SEO.
Advantages and Disadvantages
| Feature | AVIF | JPEG | PNG | WebP |
|---|---|---|---|---|
| Compression efficiency | Excellent | Moderate | Low (lossless only) | Good |
| Lossless support | Yes | No | Yes | Yes |
| Transparency (alpha) | Yes | No | Yes | Yes |
| HDR / Wide Color | Yes | Limited | No | Partial |
| Animation support | Yes | No | No (APNG only) | Yes |
| Browser support | Good (modern browsers) | Universal | Universal | Very good |
| Encoding speed | Slow | Fast | Fast | Moderate |
| Royalty-free | Yes | Yes | Yes | Yes |
The most notable drawback of AVIF is its slow encoding speed. Generating an AVIF file, especially at high quality settings, can take considerably longer than encoding a JPEG or PNG. Decoding performance has improved with hardware acceleration, but older devices and software may still struggle. Additionally, while browser support is now solid, some legacy tools and CMS platforms have limited or no native AVIF support.
How to Open and View AVIF Files
Support for AVIF has grown rapidly. Here is a list of common applications that can open and display AVIF files:
- Google Chrome (version 85 and later) – native browser support
- Mozilla Firefox (version 93 and later) – native browser support
- Apple Safari (version 16 and later) – native support on macOS and iOS
- Microsoft Edge (Chromium-based versions) – native support
- Windows 11 Photos App – native AVIF viewing support
- macOS Preview (macOS Ventura and later)
- GIMP (version 2.10.22 and later) – open-source image editor
- Adobe Photoshop (with the AV1 codec plugin or version 23.2+)
- IrfanView – lightweight viewer with AVIF support via plugins
- XnView MP – multi-format image viewer with AVIF support
- Squoosh – browser-based image tool by Google
How to Convert AVIF Files Online
If you need to convert an AVIF image to a more widely compatible format — or convert a JPEG, PNG, or WebP into AVIF — online conversion tools offer a quick and accessible solution without requiring any software installation.
Metric Converter (metric-converter.com) provides a free, browser-based image conversion tool that supports AVIF alongside dozens of other image formats. You can upload your AVIF file and convert it to JPEG, PNG, WebP, or other common formats in just a few clicks. The tool is straightforward to use: simply select your file, choose your target format, and download the converted result. This is particularly useful when you need to share images with users or platforms that don't yet support AVIF natively.
When choosing an online converter, look for tools that respect your privacy by not permanently storing uploaded files, and that support batch conversion if you need to process multiple images at once.
Frequently Asked Questions
Is AVIF better than WebP?
In most cases, yes — AVIF achieves better compression than WebP at equivalent quality levels, and it offers superior support for HDR, wide color gamut, and higher bit depths. However, WebP has broader software compatibility and encodes significantly faster, which makes it a practical choice in many workflows where encoding speed or legacy support matters.
Can I use AVIF images on my website today?
Yes, with some caveats. All major modern browsers support AVIF, but you should use the HTML <picture> element to provide fallback formats (such as WebP or JPEG) for users on older browsers or devices. This ensures all visitors see your images regardless of their browser version.
Does AVIF support transparent backgrounds?
Yes. AVIF fully supports an alpha channel for transparency, making it a viable alternative to PNG for images that require transparent or semi-transparent backgrounds. Its superior compression means transparent AVIF images are typically much smaller than equivalent PNGs.
Why is AVIF encoding so slow?
AVIF encoding is computationally intensive because the AV1 codec was originally designed for video compression, where encoding can be distributed across many frames over time. Encoding a single still image using AV1 requires running complex algorithms that are simply more demanding than those used by JPEG or PNG encoders. Encoding speed has improved with newer encoder versions and hardware acceleration support, but it remains slower than most competing formats at the highest quality settings.