EngineeringScore
Performance Larger effort

Speed up page load time

Navigation time (how long it takes from clicking a link to the page becoming usable) is one of the strongest predictors of whether a visitor stays or leaves: studies consistently show abandonment rising sharply past just a couple of seconds. It is also the most common check that requires investigating multiple causes at once rather than one single fix.

Why it matters

Slow page loads are one of the strongest predictors of visitors leaving before the page even finishes loading, directly costing traffic and conversions.

How to fix

  1. 1 Profile server response time (TTFB) and fix slow backend queries or endpoints.
  2. 2 Eliminate render-blocking CSS/JS in the critical rendering path.
  3. 3 Reduce and defer large assets that delay the largest contentful paint.

Common mistakes

  • Chasing frontend optimizations (image compression, bundling) while the real bottleneck is slow server response time (TTFB) from an unoptimized backend query.
  • Fixing the causes visible in a lab tool (Lighthouse) but not validating against real-world field data, which can differ significantly due to actual user network conditions.
  • Optimizing the homepage only, while other high-traffic pages (product pages, checkout) remain slow.

How to verify

  1. 1 Run the page through a lab tool (Lighthouse, WebPageTest) and note server response time, render-blocking resources, and largest contentful paint.
  2. 2 Check real-user monitoring / field data (e.g. Chrome UX Report, an RUM tool) if available, since lab results do not always match real conditions.
  3. 3 Re-test after each fix to confirm the specific bottleneck identified was actually resolved, not just that the page "feels" faster.

Related checks

Performance Render BlockingPerformance Page WeightPerformance Text Compression

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