WebP vs JPEG vs AVIF: When to Use Which Format
Updated: 2025-10-18
Choosing the right image format has become more nuanced in 2025. We now have three primary options for photographs and graphics on the web: JPEG, WebP and AVIF. Each has its own strengths and ideal scenarios. This guide compares their features, compression efficiency and browser support to help you pick the right tool for the job.
The contenders
JPEG: the legacy fallback
JPEG is universally supported and decodes quickly, making it indispensable as a last resort. However, it lacks transparency and animation support and typically results in larger files than modern formats【483188929336708†L45-L52】. Use JPEG for older browsers or when your pipeline cannot produce WebP or AVIF.
WebP: the modern all‑rounder
Developed by Google, WebP supports both lossy and lossless modes, alpha transparency, animation and metadata【483188929336708†L45-L57】. It’s near‑universally supported on modern browsers in 2025【483188929336708†L45-L64】. WebP images are about 25–34 % smaller than equivalent JPEGs at similar quality levels【171508693852780†L241-L290】. Decoding and encoding are relatively fast, making WebP a good default when you need broad compatibility and better compression than JPEG【401814846636866†screenshot】.
AVIF: the compression champion
AVIF is based on the AV1 video codec and offers exceptional compression. Independent testing shows that AVIF images can be roughly 50 % smaller than JPEG files【221654481411971†screenshot】, and often smaller than WebP【221654481411971†screenshot】. AVIF also supports high dynamic range (HDR), wide colour gamuts and deeper bit depths, plus alpha transparency【483188929336708†L60-L64】. Browser support is widespread but slightly behind WebP (around 93.8 % vs 95.2 %)【111889046720395†screenshot】, and encoding is computationally heavier【401814846636866†screenshot】. Use AVIF whenever you need maximum compression and advanced colour features and are willing to provide fallbacks.
Comparison summary
The table below summarises the main differences:
| Feature | JPEG | WebP | AVIF |
|---|---|---|---|
| Compression efficiency vs JPEG | — | 25–34 % smaller【171508693852780†L241-L290】 | ≈50 % smaller【221654481411971†screenshot】 |
| Lossless support | No | Yes | Yes |
| Transparency (alpha) | No | Yes | Yes |
| Animation support | No | Yes | Limited (image sequences) |
| HDR & wide colour | Limited | Typically 8‑bit | 10/12‑bit; HDR【483188929336708†L60-L64】 |
| Decoding speed | Fast | Faster | Slower【401814846636866†screenshot】 |
| Browser support (2025) | Universal | ~95 %【111889046720395†screenshot】 | ~93 %【111889046720395†screenshot】 |
When to use each format
- Use AVIF for photos and hero images when you want the smallest possible files and your visitors use modern browsers. AVIF’s superior compression and HDR support make it ideal for high‑impact visuals.
- Use WebP as a universal fallback for both photos and graphics. It balances compression, speed and features and is supported by almost all browsers【111889046720395†screenshot】.
- Use JPEG as a legacy fallback when older browsers or tools require it or when progressive decoding is desirable.
- For icons and diagrams consider SVG for infinitely scalable, crisp graphics. Use lossless WebP or PNG for rasterised UI art.【483188929336708†L33-L37】
Implementation tips
Always use the <picture> element to specify
multiple sources. Place AVIF first, followed by WebP and then JPEG.
Set explicit dimensions and use responsive srcset
values to avoid sending oversized images to mobile users【483188929336708†L150-L176】.
Preload your largest hero image if it is critical to the first
paint, but avoid preloading multiple variants to prevent duplicate
downloads【483188929336708†L178-L185】.
Conclusion
With modern formats becoming mainstream, there’s no reason to rely solely on JPEG in 2025. AVIF should be your go‑to for premium photography, WebP serves as a flexible default, and JPEG remains a last‑ditch safety net. By understanding the trade‑offs and implementing proper fallbacks, you can deliver beautiful images without slowing down your site.