AVIF (AV1 Image File Format) is a modern image format developed by the Alliance for Open Media and released in 2019. It uses the AV1 video codec's compression algorithm — the same technology behind efficient video streaming — applied to still images. The result is significantly smaller file sizes than JPEG, PNG, and even WebP, at equivalent or better visual quality. As of 2026, AVIF is supported in all major browsers and has become a serious option for web image optimization.

How AVIF Compresses Images

AVIF uses the AV1 codec's intra-frame compression, which is substantially more sophisticated than older approaches:

Larger transform blocks: AV1 analyzes up to 128×128 pixel regions at once (JPEG uses 8×8). Larger blocks capture more spatial patterns, enabling better prediction of smooth gradients and large uniform areas.
Advanced prediction modes: Over 50 directional prediction modes to extrapolate pixels from neighboring blocks, vs. JPEG's simpler DCT-only approach.
Loop filters and post-processing: In-loop deblocking and constrained directional enhancement filters reduce compression artifacts at the codec level.
Perceptual quality optimization: AVIF encoders can target perceptual quality metrics (SSIM, VMAF) rather than raw bit count, producing better-looking images at the same file size.

AVIF supports both lossy and lossless compression, alpha channel (transparency), HDR (high dynamic range), wide color gamut, and animated sequences.

AVIF vs WebP vs JPEG — File Size Comparison

Approximate file sizes for representative images at visually similar quality:

Photograph (equivalent quality): AVIF ≈ 300 KB | WebP ≈ 400 KB | JPEG ≈ 550 KB | PNG ≈ 2 MB
Logo with transparency: AVIF (lossless) ≈ 22 KB | WebP (lossless) ≈ 30 KB | PNG ≈ 45 KB
Short animation (3 sec): Animated AVIF ≈ 200 KB | Animated WebP ≈ 300 KB | GIF ≈ 2 MB

These are approximations — actual savings depend on image content. AVIF gains are largest on photos with complex gradients. Simple flat-color graphics show less difference.

AVIF Browser Support

As of 2026, AVIF has broad browser support:

Full support: Chrome 85+, Firefox 93+, Safari 16+, Edge 121+, Opera 71+, Chrome Android, Safari iOS 16+
No support: Internet Explorer (no longer relevant), some older Android WebViews, Office applications
Partial / slow encoding: Older devices may display AVIF but decode slowly; keep fallbacks for critical path images

Safari added AVIF support in version 16 (late 2022). As of 2026, Safari 16+ represents the vast majority of active Safari usage, making AVIF safe for most web projects.

AVIF vs WebP — Which Should You Use?

Both are better than JPEG for web use. The key differences:

File size: AVIF is typically 20–30% smaller than WebP at equivalent quality. For bandwidth-constrained users, this matters.
Encoding speed: AVIF encoding is slower than WebP — sometimes significantly so for high-quality settings. This matters for on-the-fly image CDNs.
Browser compatibility: WebP has slightly broader support (Chrome 32+, Safari 14+). AVIF requires Chrome 85+ and Safari 16+. For most sites in 2026, both are safely usable.
Tooling: WebP has better tooling coverage — more image editors, CDNs, and build pipelines support WebP natively. AVIF support is improving but not universal.

Recommendation: Use AVIF where maximum compression matters and encoding time is acceptable (static assets, pre-built images). Use WebP where encoding speed or broader compatibility is a priority.

When to Use AVIF

Website hero images and product photos: AVIF's superior compression reduces LCP (Largest Contentful Paint) times, directly improving Core Web Vitals scores.
Next.js and modern frameworks: Next.js's next/image serves AVIF automatically when the browser supports it (configured via formats: ['image/avif', 'image/webp'] in next.config.js).
E-commerce product images: Large catalogs benefit most from smaller file sizes — fewer bytes per image multiplies across thousands of products.
HDR and wide gamut content: AVIF natively supports 10-bit and 12-bit color depth, making it the only common web format that handles HDR photography well.

When Not to Use AVIF

Email: Email clients don't render AVIF. Use JPG or PNG for email images.
Office documents: Word, PowerPoint, and Excel don't support AVIF insertion. Use PNG or JPG.
Social media uploads: Instagram, Twitter/X, Facebook, and LinkedIn convert uploaded images to JPEG internally. Upload JPG directly to avoid double compression.
Image editing workflows: Don't use AVIF as a working file format. Save originals as TIFF or PSD; export to AVIF only for final web delivery.
Performance-sensitive on-the-fly generation: AVIF encoding is CPU- intensive. If you generate images server-side at request time, WebP or JPG may be more practical.

How to Convert Images to AVIF

You can convert any image to AVIF for free in your browser:

All conversions run in the browser — nothing is uploaded to a server.

How to Convert AVIF to Other Formats

If you receive an AVIF file and need a more compatible format:

AVIF to JPG — for photos, email, social media
AVIF to PNG — for logos, screenshots, documents

What File Extension Does AVIF Use?

AVIF files use the .avif extension and the MIME type image/avif. They cannot be renamed to .jpg or .png — the file format is different and renaming just corrupts the file. You need to actually convert it.

AVIF vs JPEG XL — What's the Difference?

JPEG XL (JXL) is another next-generation format that competes with AVIF. JPEG XL offers lossless recompression of existing JPEGs (useful for archives), faster encoding than AVIF, and comparable compression ratios. However, Chrome removed JPEG XL support in 2022 and browser adoption remains limited. As of 2026, AVIF has significantly better browser support than JPEG XL for web deployment.