Convert images to WebP or AVIF — Cursor
JPEGs and PNGs are larger than they need to be in 2026. WebP and AVIF cut sizes by 30-50% at the same visual quality — meaningful LCP improvement.
Fixing this in Cursor
Agentic AI code editor built on VSCode
In Cursor you edit real files, so this fix lands via direct diffs instead of a regenerated project. Paste the prompt below into your Cursor chat and the fix rolls out across the project in one pass.
Using a different tool? Pick your stack:
The prompt for Cursor
Copy and paste this into your Cursor chat exactly as-is.
Apply these changes to my codebase. Edit the files directly and keep existing formatting: Use modern image formats 1. Convert JPEG/PNG images to WebP or AVIF format. 2. Use <picture> element with fallback for older browsers.
Why this matters
Modern image formats are the #1 lever for image-heavy pages. A 2MB hero JPEG becomes a 500KB WebP with no visible quality loss — ~1.5 seconds off LCP on mobile.
Every modern browser supports WebP (99%+ coverage). AVIF has lower support but is 30% smaller than WebP when it works.
How to use this prompt in Cursor
- 1. Open your Cursor project.
- 2. Copy the prompt above with the copy button.
- 3. Paste into the Cursor chat and send.
- 4. Review the diff, accept the changes, redeploy.
- 5. Verify the fix using the checklist below.
Common mistakes to avoid
- error_outlineConverting but keeping JPEG originals as the primary format.
- error_outlineOver-compressing — artifacts become visible.
- error_outlineNot using `<picture>` with fallback for safety.
How to verify the fix worked
- check_circleChrome DevTools → Network → Img type → sizes reduced.
- check_circleLighthouse → "Serve images in next-gen formats" passes.
- check_circlePageSpeed Insights shows image opportunities gone.
Frequently asked questions
WebP or AVIF?expand_more
Do I lose quality?expand_more
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