How to speed up your website with image compression
If your site feels slow, images are almost certainly the cause — they're typically 50%+ of page weight. Here's a concrete plan that takes an afternoon and delivers the biggest speed gain per hour of effort.
Step 1: Audit your heaviest images
Open DevTools → Network → filter by Img, reload, and sort by size. The biggest offenders are usually the hero image and product/gallery photos.
Step 2: Convert to WebP at 82%
WebP cuts 25-35% versus JPG. Run your images through JPG to WebP or the compressor at 82% quality.
Step 3: Right-size everything
Cap images to the largest size they actually display — usually 1920px wide for full-bleed, much less for thumbnails. Use the resizer. This alone often halves file size.
Step 4: Bulk-process the whole library
For an existing site, drop your entire /images folder into bulk compress and download one ZIP. Replace the originals.
Step 5: Lazy-load and set dimensions
Add loading="lazy" to below-the-fold images and always set width/height to prevent layout shift.
What to expect
In our testing, converting a typical gallery to right-sized WebP improved mobile Lighthouse performance by 18-32 points. See the deeper dive: why file compression improves website speed.