AVIF

AV1 Image File Format

image/avif Released 2019 · by Alliance for Open Media (AOMedia)

AVIF is a next-generation image format based on the AV1 video codec, delivering exceptional compression efficiency and support for HDR, wide color gamut, and animation — significantly outperforming both JPEG and WebP in quality-to-size ratio.

Web Transparency Animation ✦ HDR Production Ready

Technical Specifications

MIME Type

image/avif

Extensions

.avif

Container

HEIF / ISOBMFF

Compression

AV1 Lossy & AV1 Lossless

Algorithms

AV1

Color Depth

8-bit, 10-bit, 12-bit

Metadata

EXIF XMP ICC

Capabilities

Transparency

Animation

Progressive Loading

Alpha Channel

HDR Support

Official Specification

Magic Bytes & HTTP Headers

File Signature (Magic Bytes)

XX XX XX XX 66 74 79 70 61 76 69 66

ASCII: ....ftypavif

HTTP Headers

Content-Type: image/avif

HTML Accept Attribute

accept="image/avif"

Browser Support Matrix

Browser	Status	Min Version
Chrome	Supported	85+
Firefox	Supported	93+
Safari	Supported	16+
Edge	Supported	121+
Internet Explorer	Not Supported	Legacy

Advantages & Limitations

Advantages

Best-in-class compression — typically 20–50% smaller than WebP at equivalent quality
Native HDR and wide color gamut (BT.2020) support
Supports 8, 10, and 12-bit color depth

Limitations

Encoding is highly CPU-intensive — significantly slower than JPEG or WebP
Requires Edge 121+ (not supported in earlier Edge versions)
Limited support in native desktop image viewers

Developer Code Snippets

import magic
print(magic.from_file('file.avif', mime=True)) # Outputs 'image/avif'

const FileType = require('file-type');
const type = await FileType.fromFile('file.avif');
console.log(type.mime); // image/avif

// Go standard library doesn't detect AVIF natively.
// Use github.com/h2non/filetype instead:
kind, _ := filetype.Match(buf)
fmt.Println(kind.MIME.Value) // image/avif

$mime = mime_content_type('file.avif');
echo $mime; // image/avif

File Detection Steps

How to programmatically detect a image/avif file by reading its raw bytes:

1 Check for ISOBMFF 'ftyp' box at offset 4
2 Verify 'avif' or 'avis' brand string at offset 8

Software Support

Google Chrome

Mozilla Firefox

Apple Safari

GIMP 2.10+

ImageMagick 7.0.25+

Squoosh

Cloudinary

Conversion Tools

Share & Embed

Markdown Badge

[![AVIF Format](https://freewebptojpg.com/mime/image/avif/badge.svg)](https://freewebptojpg.com/mime/image/avif)

Interactive iframe Widget

<iframe src="https://freewebptojpg.com/mime/image/avif/embed" width="100%" height="280" style="border:1px solid #cbd5e1;border-radius:8px;" title="AVIF Specs"></iframe>

JSON API

All data on this page is available as a free, open JSON API. Use it in your project, documentation, or tooling.

GET https://freewebptojpg.com/mime/image/avif.json Open JSON

Free to use

No auth required

CORS enabled

Use from any domain

Cached 24h

Cache-Control headers set

Frequently Asked Questions

What is the magic byte for AVIF?

AVIF uses the ISOBMFF container. The signature starts with a variable-length box size, followed by 66 74 79 70 61 76 69 66 (ftypavif). Full hex: XX XX XX XX 66 74 79 70 61 76 69 66.

Is AVIF better than WebP?

AVIF generally provides 20–50% better compression than WebP at equivalent visual quality, especially at lower bitrates. However, AVIF encoding is significantly slower and browser support, while growing, is slightly behind WebP.

Does AVIF support HDR?

Yes, AVIF natively supports HDR (High Dynamic Range) and wide color gamuts including BT.2020, making it ideal for modern photography and display-quality images.