WebP vs JPEG: Why Your Image Format Still Matters
JPEG has dominated the web for 30 years, but WebP is smaller, faster, and supported by every modern browser. Here's what you need to know.
The short version
A WebP image is typically 25–35% smaller than an equivalent JPEG at the same visual quality. On a page with 20 images, that's potentially 5 MB of data you're not making your users download.
What is WebP?
WebP is an image format developed by Google and released in 2010. It uses both lossy and lossless compression and supports transparency (like PNG) and animation (like GIF) — all in a single format.
Browser support is no longer a concern. Chrome, Firefox, Safari (since 2020), and Edge all support WebP. Globally, WebP support covers over 97% of web users.
How does the file size difference actually play out?
Here's a real-world comparison of the same photograph compressed to visually similar quality:
| Format | File Size | Quality Setting | |--------|-----------|-----------------| | JPEG | 420 KB | 85 | | WebP | 285 KB | 85 | | WebP | 210 KB | 75 |
The 75-quality WebP is roughly half the size of the JPEG and looks identical at normal viewing distances.
For photographic content, expect 25–40% savings. For graphics, screenshots, and UI elements with flat colours, the savings can reach 50–70%.
What about AVIF?
AVIF is the next-generation format with even better compression than WebP. The catch: encoding AVIF is computationally expensive, and browser support (while growing) is less universal than WebP. For most sites, WebP is the better choice today.
The case for automatic conversion
Manually converting every image to WebP isn't practical. The right approach is to serve WebP automatically to browsers that support it, and fall back to JPEG for the rare browser that doesn't.
This is exactly what a good image CDN does — you upload once, it serves the right format to each visitor automatically.
Key takeaways
- WebP gives you smaller files with the same or better visual quality
- Browser support is essentially universal in 2025
- Manual conversion doesn't scale — automate it at the CDN level
- The average page can save 1–5 MB by switching to WebP
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