Software EngineeringEngineeringPlatinum

Improve your website's loading speed and user experience.

Core Web Vitals Optimizer

Core Web Vitals, LCP, CLS, INP

1 activationsexpertv5.0

Best for

▸Diagnosing slow Largest Contentful Paint (LCP) caused by render-blocking resources or TTFB issues
▸Fixing Cumulative Layout Shift (CLS) from images without dimensions or dynamic content injection
▸Optimizing Interaction to Next Paint (INP) by identifying long tasks and main thread bottlenecks
▸Prioritizing performance fixes based on expected Core Web Vitals impact and implementation effort

What you'll get

▸Diagnostic report identifying TTFB as root cause of 3.8s LCP, with CDN configuration and server response optimization steps
▸CLS fix prioritization matrix ranking image dimension fixes (0.15 improvement) over font optimization (0.03 improvement)
▸INP optimization plan targeting specific JavaScript bundles and event handler refactoring with expected sub-200ms results

Expects

Current Core Web Vitals scores (lab and field data), website URL or performance audit results, and specific failing metrics with context about the site's tech stack.

Returns

Prioritized action plan with specific fixes, expected metric improvements, and implementation steps focused on LCP, CLS, and INP optimization.

What's inside

“You are a Core Web Vitals Performance Engineer. You optimize production websites to achieve passing Core Web Vitals scores by systematically diagnosing performance bottlenecks, prioritizing high-impact fixes, and validating improvements through rigorous measurement. - **Distinguish field data from l...”

Covers

What You Do DifferentlyMethodologyWatch For

Not designed for ↓

×General website speed improvements unrelated to Core Web Vitals metrics
×Backend API performance optimization or database query tuning
×Mobile app performance or native application optimization
×SEO improvements beyond page speed ranking factors

SupaScore

89.45▼

Research Quality (15%)

9.25

Prompt Engineering (25%)

8.85

Practical Utility (15%)

8.7

Completeness (10%)

9.4

User Satisfaction (20%)

8.9

Decision Usefulness (15%)

8.8

Evidence Policy

Standard: no explicit evidence policy.

core-web-vitalslcpclsinppage-speedperformance-optimizationlighthouseweb-performancettfbfrontend-performancecruxresource-hints

Research Foundation: 8 sources (5 official docs, 2 industry frameworks, 1 web)

This skill was developed through independent research and synthesis. SupaSkills is not affiliated with or endorsed by any cited author or organisation.

Version History

v5.03/25/2026

v5.5 distilled from v2 via Claude Sonnet

v2.02/21/2026

Pipeline v4: rebuilt with 3 helper skills

v1.0.02/16/2026

Initial release

Works well with

API Performance Testing ExpertPlatinum Bundle Analysis ExpertPlatinum Caching Strategy ArchitectPlatinum Frontend Observability EngineerPlatinum Image Optimization Pipeline ExpertPlatinum

Need more depth?

Specialist skills that go deeper in areas this skill touches.

CDN Edge Computing ArchitectPlatinum Load Testing StrategistPlatinum Database Performance TunerPlatinum

Common Workflows

Complete Performance Audit & Fix

Comprehensive performance optimization from Core Web Vitals diagnosis through specific asset optimization to ongoing monitoring setup

core-web-vitals-optimizer→Bundle Analysis Expert→Image Optimization Pipeline Expert→Frontend Observability Engineer