If your Core Web Vitals are struggling right now, you are not alone and you probably do not need a full rebuild.
Most teams get wins by doing a handful of boring, high-impact fixes in the right order, then locking them in so they do not regress next sprint.
This guide is built for teams that need to move quickly, show real impact, and keep performance gains after launch week.
The thresholds that matter
Google's "good" thresholds are still the practical baseline:
- LCP at p75: 2500ms or less
- INP at p75: 200ms or less
- CLS at p75: 0.1 or less
Treat these like service targets, not one-off Lighthouse trophies.
Field data vs lab data
The most common trap is chasing one great Lighthouse run while real users are still waiting on mobile.
Use both:
- Field data (CrUX / Search Console): what users actually experience over 28 days
- Lab data (Lighthouse / WebPageTest): fast debugging while you build fixes
If they disagree, trust field data for roadmap decisions.
A 30-day execution plan
Days 1-3: Establish a baseline
- Pull current p75 metrics for core templates (home, landing, pricing, checkout, dashboard).
- Split by device class (mobile and desktop).
- List your biggest offenders by URL pattern.
Output to aim for:
- A focused list of 5 to 10 high-impact templates
- One owner per template
Days 4-10: Fix LCP first
LCP is often the fastest conversion and bounce-rate win.
Common levers:
- Compress and resize hero images
- Serve modern formats where possible
- Preload only the true LCP element
- Improve TTFB via caching and backend query cleanup
- Remove render-blocking CSS and non-critical JS from above the fold
Days 11-18: Fix INP
INP issues usually come from long main-thread tasks and heavy client-side scripting.
Common levers:
- Reduce JavaScript payload size
- Break long tasks into smaller async work
- Lazy-hydrate non-critical components
- Remove third-party scripts that are not business-critical
Days 19-24: Fix CLS
CLS failures are usually consistency issues in templates and ad slots.
Common levers:
- Reserve width/height for images and embeds
- Keep ad and promo slots dimensioned before load
- Avoid injecting content above existing content after paint
Days 25-30: Lock in and prevent regression
- Add performance budgets to CI/CD
- Add release checklist gates for templates touching hero, nav, or ads
- Re-scan after each deploy and review trend deltas weekly
Owner checklist
- [ ] Every high-traffic template has a named performance owner.
- [ ] LCP, INP, and CLS targets are defined per template, not just site-wide.
- [ ] Post-release scans are mandatory for performance-related changes.
- [ ] Weekly trend review is on the calendar.
Where Scavo helps
Scavo combines page speed checks with Core Web Vitals context, so you can choose fix order with less guesswork:
- First fix what hurts real users (field data).
- Then remove technical blockers causing repeat regressions.
That sequence turns "we ran an audit" into "we moved p75 and kept it there."
Sources
What to do next in Scavo
- Run a fresh scan on your main domain.
- Open the matching help guide in
/help, assign an owner, and ship the smallest safe fix. - Re-scan after deployment and confirm the trend is moving in the right direction.
