Quick Performance Audit
A fast check of the biggest performance bottlenecks. Target time: under 1 hour.
For a comprehensive audit, see the full Performance audit.
1. Lighthouse Score
Go to PageSpeed Insights, paste the URL for the homepage and 2–3 key pages, and run the test. This gives you a performance score out of 100 and measures the Core Web Vitals:
- LCP (Largest Contentful Paint) — how fast the main content appears
- CLS (Cumulative Layout Shift) — how much the page jumps around while loading
- INP (Interaction to Next Paint) — how quickly the page responds to clicks
2. Largest Contentful Paint (LCP)
The LCP element is usually the hero image or the main headline — the biggest thing the user sees first. In the PageSpeed Insights report, it tells you what the LCP element is.
A common mistake is lazy-loading the hero image. Lazy-loading tells the browser “don’t load this until the user scrolls to it”, which delays the most important content. The LCP element should always load immediately.
3. Image Optimization
Open Chrome DevTools (F12), go to the Network tab, and reload the page. Click the Img filter to show only images. Look for:
- Large file sizes — images over 200 KB are worth checking. Are they bigger (in pixels) than they need to be?
- Old formats — modern formats like WebP and AVIF are much smaller than PNG/JPG at the same quality
- Missing dimensions — images without
widthandheightattributes cause the page to jump around as they load (this is what CLS measures)
4. Render-Blocking Resources
In the PageSpeed Insights report, look for the “Eliminate render-blocking resources” opportunity. These are CSS and JavaScript files in the <head> that the browser must fully download before it can show anything on screen. Large blocking resources mean a slower first paint.
5. Caching Headers
When a browser downloads an image or CSS file, caching headers tell it how long to keep that file before re-downloading it. In the DevTools Network tab, click on a static asset (image, CSS, JS file) and look at the Response Headers for Cache-Control. Static assets should have long cache durations (e.g. max-age=31536000). If there’s no Cache-Control header, repeat visitors re-download everything.
6. Total Page Weight
At the bottom of the DevTools Network tab, you’ll see the total transfer size. This is how much data the page loads. A page over 3 MB is worth flagging. Note what takes up the most space — usually images or JavaScript bundles.