JPEG vs WebP vs AVIF in WordPress: Real Benchmark Data (4 Plugins Tested)

TL;DR: I benchmarked 4 image optimization plugins on the exact same WordPress install with the same source image, all tested on lossy mode . AVIF is the clear winner format, up to 91% compression. The differences between plugins are bigger than the marketing suggests. Full data tables below Why I Did This I got tired of vague comparisons with no real numbers. So I set up a controlled test, same server, same WordPress install, same source image, and ran every major image optimization plugin through the same benchmark. No affiliate links. Just numbers. Test Setup Source image: Single JPEG, 2400×1590px — a real-world photo, not a tiny thumbnail. Plugins tested: ShortPixel, Imagify, Optimole, EWWW Image Optimizer Method: Each plugin processed the same source file with lossy mode (most aggressive available). Output files downloaded and measured directly. Results JPEG Compression (Lossy) Plugin Output Reduction Verdict 🏆 ShortPixel (Lossy) 89 KB 82.0% 🟢🟢🟢🟢🟢 🥈 Imagify (Lossy) 119 KB 75.9% 🟡🟡🟡