I use some perf checklists whenever I review a site. Here’s the incomplete list.

Inspired by / forked from Dilip Siva’s perf checklist and AMP project!.

Web Performance Checklist

  • Prefer Brotli over gzip / deflate.
  • Check caching-headers for all static content (css, js, images, fonts, icons, etc).
  • Avoid free DNS from your DNS registrar (there are exceptions, of course).
  • Try hosting your whole site in a CDN.
  • Reduce the number of DOM elements.


  • Use a single resource for loading external JavaScript.


Images checklist

  • Prefer WebP for images over PNG / Jpeg.
  • Use a CDN for image-heavy sites.
  • Serve small images for mobile users.

Fonts checklist

  • Do not use more than 2 external fonts (unless really really necessary on special circumstances).
  • Load fonts asynchronously.
  • Have plan B if the internet speed is too low!