Best Image Formats for Web in 2025
Pick the wrong image format and your website crawls like it's 2010. Pick the right one? Lightning fast, crystal clear. Here's how to choose between JPG, PNG, WebP, and AVIF without overthinking it.
Why Format Choice Matters
Images eat up like 50-70% of your page's total size. Yeah, way more than your code. The format you pick directly impacts how fast your site loads, whether people stick around, and—here's a fun one—your Google ranking. They literally factor page speed into search results.
But it's not just about making files smaller. Different formats handle different stuff: transparency, animations, whether you're dealing with photos or graphics. Use the wrong one and you get blurry images, massive files, or features that just... don't work.
JPEG (JPG): The Photo Workhorse
JPEG's been around since 1992 and it's still the go-to for photos. Uses lossy compression, which sounds scary but basically means it throws away data your eyes won't miss anyway. Smart, honestly.
Best For:
- Photographs and realistic images
- Images with smooth gradients and many colors
- When file size is more important than perfect quality
Avoid For:
- Images with text or sharp lines (creates blurry artifacts)
- Logos and icons
- Images needing transparency
JPEG Quality Tips
- Quality 80-85% is the sweet spot—minimal visible loss, significant size reduction
- Quality 60-70% for thumbnails or background images where quality is less critical
- Below 50% usually shows noticeable artifacts and isn't recommended
PNG: The Transparency Champion
PNG doesn't throw away any data—what you put in is exactly what you get out. Lossless compression. It's also got full alpha channel transparency, which is fancy talk for "backgrounds can be see-through."
Best For:
- Images needing transparency (logos on varied backgrounds)
- Graphics with sharp lines, text, or solid colors
- Screenshots and diagrams
- When you need to edit/re-save without quality loss
Avoid For:
- Photographs (file sizes will be 5-10x larger than JPEG)
- When bandwidth is a concern
PNG-8 vs PNG-24: PNG-8 supports only 256 colors (like GIF) and produces smaller files. PNG-24 supports 16 million colors and full transparency, but larger files. Most tools export PNG-24 by default.
WebP: The Modern Hybrid
Google made WebP back in 2010 and honestly? It's pretty great. Combines the best parts of JPEG and PNG—lossy compression, lossless compression, transparency support, all while being smaller than both.
The Numbers:
- WebP lossy is typically 25-34% smaller than JPEG at equivalent quality
- WebP lossless is typically 26% smaller than PNG
Best For:
- All web images where browser support isn't a concern
- Replacing both JPEG and PNG with one format
- Performance-critical websites
Considerations:
- Supported by all modern browsers (Chrome, Firefox, Safari, Edge)
- Some older browsers and image editors don't support it
- Social media platforms may re-encode WebP uploads
AVIF: The New Contender
AVIF is the new kid on the block (2019) and it's seriously impressive for compression. Even better than WebP, especially if you're dealing with photos.
The Numbers:
- AVIF is typically 50% smaller than JPEG
- About 20% smaller than WebP
Best For:
- Cutting-edge performance optimization
- High-resolution photography
- Sites targeting modern browsers only
Considerations:
- Slower to encode than WebP or JPEG
- Browser support is still growing (2024: ~92% global support)
- Some quality issues with very low bitrates
Format Comparison Table
| Feature | JPEG | PNG | WebP | AVIF |
|---|---|---|---|---|
| Compression | Lossy | Lossless | Both | Both |
| Transparency | No | Yes | Yes | Yes |
| Animation | No | No* | Yes | Yes |
| Photo Quality | Good | Perfect | Better | Best |
| File Size | Medium | Large | Small | Smallest |
| Browser Support | 100% | 100% | ~97% | ~92% |
*APNG exists but isn't widely used
Practical Recommendations for 2025
For Photos (Hero images, product shots, blog images):
- First choice: WebP with quality 80-85%
- With fallback: JPEG for older browsers
- If file size is critical: Consider AVIF for modern browsers
For Graphics (Logos, icons, illustrations):
- With transparency: PNG-24 or WebP lossless
- Without transparency: PNG-8 if 256 colors sufficient, else PNG-24
- For very simple graphics: Consider SVG (vector format, infinitely scalable)
For Thumbnails and Low-Priority Images:
- More aggressive compression is acceptable
- JPEG quality 60-70% or WebP quality 70%
- Consider lazy loading to defer off-screen images
The "Picture" Element: Best of All Worlds
Modern HTML has this cool trick where you can serve different image formats to different browsers using the <picture> element:
<picture> <source srcset="image.avif" type="image/avif"> <source srcset="image.webp" type="image/webp"> <img src="image.jpg" alt="Description"> </picture>
The browser just picks the first format it understands. So browsers that support AVIF get the smallest file, WebP-capable ones get the next best option, and everyone else gets good old reliable JPEG. Pretty smart.