Web performance audits measure load times, identify bottlenecks, and guide optimization efforts to create faster, better user experiences.
When to Use
Regular performance monitoring
After major changes
User complaints about slowness
SEO optimization
Mobile optimization
Performance baseline setting
Quick Start
Minimal working example:
Core Web Vitals (Google):
Largest Contentful Paint (LCP):
Measure: Time to load largest visible element
Good: <2.5 seconds
Poor: >4 seconds
Impacts: User perception of speed
First Input Delay (FID):
Measure: Time from user input to response
Good: <100 milliseconds
Poor: >300 milliseconds
Impacts: Responsiveness
Cumulative Layout Shift (CLS):
Measure: Visual stability (unexpected layout shifts)
Good: <0.1
Poor: >0.25
Impacts: User frustration
---
Additional Metrics:
First Contentful Paint (FCP):
// ... (see reference guides for full implementation)
Reference Guides
Detailed implementations in the references/ directory:
Guide
Contents
Performance Metrics
Performance Metrics
Performance Analysis Process
Performance Analysis Process
Optimization Strategies
Optimization Strategies
Monitoring & Continuous Improvement
Monitoring & Continuous Improvement
Best Practices
✅ DO
Measure regularly (not just once)
Use field data (real users) + lab data
Focus on Core Web Vitals
Set realistic targets
Prioritize by impact
Monitor continuously
Setup performance budgets
Test on slow networks
Include mobile in testing
Document improvements
❌ DON'T
Ignore field data
Focus on one metric only
Set impossible targets
Optimize without measurement
Forget about images
Ignore JavaScript costs
Skip mobile performance
Over-optimize prematurely
Forget about monitoring
Expect improvements without effort
Converted and distributed by TomeVault — claim your Tome and manage your conversions.
1---2name: aj-geddes-useful-ai-prompts-web-performance-audit3description: Web Performance Audit4---56# Web Performance Audit78## Table of Contents910- [Overview](#overview)11- [When to Use](#when-to-use)12- [Quick Start](#quick-start)13- [Reference Guides](#reference-guides)14- [Best Practices](#best-practices)1516## Overview1718Web performance audits measure load times, identify bottlenecks, and guide optimization efforts to create faster, better user experiences.1920## When to Use2122- Regular performance monitoring23- After major changes24- User complaints about slowness25- SEO optimization26- Mobile optimization27- Performance baseline setting2829## Quick Start3031Minimal working example:3233```yaml34Core Web Vitals (Google):3536Largest Contentful Paint (LCP):37 Measure: Time to load largest visible element38 Good: <2.5 seconds39 Poor: >4 seconds40 Impacts: User perception of speed4142First Input Delay (FID):43 Measure: Time from user input to response44 Good: <100 milliseconds45 Poor: >300 milliseconds46 Impacts: Responsiveness4748Cumulative Layout Shift (CLS):49 Measure: Visual stability (unexpected layout shifts)50 Good: <0.151 Poor: >0.2552 Impacts: User frustration5354---5556Additional Metrics:5758First Contentful Paint (FCP):59// ... (see reference guides for full implementation)60```6162## Reference Guides6364Detailed implementations in the `references/` directory:6566| Guide | Contents |67|---|---|68| [Performance Metrics](references/performance-metrics.md) | Performance Metrics |69| [Performance Analysis Process](references/performance-analysis-process.md) | Performance Analysis Process |70| [Optimization Strategies](references/optimization-strategies.md) | Optimization Strategies |71| [Monitoring & Continuous Improvement](references/monitoring-continuous-improvement.md) | Monitoring & Continuous Improvement |7273## Best Practices7475### ✅ DO7677- Measure regularly (not just once)78- Use field data (real users) + lab data79- Focus on Core Web Vitals80- Set realistic targets81- Prioritize by impact82- Monitor continuously83- Setup performance budgets84- Test on slow networks85- Include mobile in testing86- Document improvements8788### ❌ DON'T8990- Ignore field data91- Focus on one metric only92- Set impossible targets93- Optimize without measurement94- Forget about images95- Ignore JavaScript costs96- Skip mobile performance97- Over-optimize prematurely98- Forget about monitoring99- Expect improvements without effort100101---102> Converted and distributed by [TomeVault](https://tomevault.io/claim/aj-geddes) — claim your Tome and manage your conversions.103<!-- tomevault:4.0:skill_md:2026-04-11 -->
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