Website Speed Optimization Guide: From 60 to 100 Lighthouse
A pragmatic 2026 website speed optimization guide — image strategy, JS budget, font loading, edge caching and the changes that actually move scores.
The website speed optimisation playbook that takes Lighthouse from 60 to 100 — without rewriting the whole frontend.
Image strategy first
Modern formats (AVIF/WebP), correct sizing, lazy loading below the fold, preload the LCP image. This alone fixes half of bad scores.
JavaScript budget
Audit third-party scripts. Defer non-critical. Replace heavy libraries with lighter alternatives. Code-split aggressively.
Font loading
Self-host. Use font-display: swap. Preload critical weights. Set fallback metrics to kill CLS.
Edge caching
Push static assets and pre-rendered HTML to the edge. TTFB under 200ms is achievable on most stacks.
Measure on real devices
Lighthouse scores are a starting point. Field data is what Google ranks on.
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Keep reading
- Core Web Vitals 2026 Deep Dive: INP, LCP and the New BarCore Web Vitals moved on. Here's the 2026 deep dive — INP fixes, LCP image strategy and the new ranking bar.
- SEO-Friendly Web Development: A Guide for DevelopersAn SEO-friendly web development guide developers actually want to read — rendering, routing, schema, performance and the JS SEO traps.
- How to Run a Technical SEO Audit (Step-by-Step Guide)The step-by-step technical SEO audit process senior consultants use — and the prioritised fix list devs actually ship.
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