Performance check
Images use modern formats
Images are served in modern formats and are not grossly oversized.
low severityperf.image-formats
Run this check on your site
Runs just this check in quick mode. The report opens with the evidence and the fix.
Why it matters
Images dominate the weight of a typical page. AVIF and WebP cut the size of a photograph by half compared with JPEG, at the same quality.
How to fix it
Serve AVIF or WebP with a fallback, resize images to the size they are displayed at, and compress them.
The details
- Category
- Performance
- Severity of a failure
- low
- Confidence
- medium
- Needs a browser
- No
- Check id
- perf.image-formats
References
Free tools that run this check
Image SEO CheckerImages without alt text are invisible to screen readers and image search. Oversized and legacy images slow the page down. Check both in one go.Page Speed TestMeasure how fast a page answers and renders on a throttled mobile profile, and find the causes: heavy pages, missing compression, uncached assets and render blocking scripts.