Measure the right things before deleting half the site
Start with field data and lab tests. Look at Largest Contentful Paint, Interaction to Next Paint, Cumulative Layout Shift, server response time, JavaScript execution, and the pages where revenue actually happens.
- Test homepage, service pages, product pages, and landing pages.
- Compare mobile and desktop separately.
- Prioritise templates that affect enquiries or sales.
Images are usually the obvious villain
Huge hero images, uncompressed uploads, missing responsive sizes, and lazy-loading mistakes can make a decent site feel like it is arriving by courier.
- Use modern formats and responsive image sizes.
- Preload the real hero image where appropriate.
- Lazy-load below-the-fold media, not critical content.
JavaScript should earn its rent
Every widget, tracker, animation library, and chat script adds cost. If a script does not help the visitor choose, trust, buy, or enquire, ask why it gets to live.
- Remove unused libraries and duplicate trackers.
- Defer non-critical scripts.
- Split code by route where the framework supports it.
Speed work is not finished until the form works faster too
A fast first paint followed by a sluggish form is a polished ambush. Test the conversion path after performance fixes, especially on mobile.
- Check tap targets and layout shift around forms.
- Measure form errors and submission speed.
- Retest after every major plugin or script change.