From beginner to expert in web performance

on YouTube ↗16m

" summary

Shows concrete steps to get realistic Lighthouse numbers: open production in incognito, set device to moto g4, throttle to 3g and 4x slowdown, disable cache, then run Lighthouse and interpret FCP (≤1.5s), LCP (≤2.5s at the 75th percentile), CLS (<0.1), TBT (<300ms) and speed index (~0–4.3s). Recommends two quick wins that actually change metrics: make images responsive and small (images under 100 kb) and remove unused code using DevTools Coverage (unused JavaScript coverage).

AI-written summary · about

" chapters (6)

1. 0:00Start
2. 1:02What are we going to talk about today?
3. 1:55Understand your demographic
4. 2:31Create your #webperf foundation
5. 4:11Measuring in Chrome DevTools & Lighthouse
6. 7:00Understanding key Lighthouse Metrics

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