Website Performance Audit Agency
Expert Website Performance Audit Services
Comprehensive website performance audit covering 50+ metrics, waterfall profiling, JavaScript CPU analysis, third-party script impact, and a prioritized action plan you can hand to any developer.
Most speed tools give you a score and a generic list of recommendations. Our performance audit goes deeper, we profile your waterfall request chain, CPU execution timeline, main-thread blocking, rendering order, cache efficiency, and real-user field data. We identify root causes, not symptoms. Every finding is prioritized by its score impact and business value, so your team knows exactly what to fix first.
Trusted by leading brands
Our Expertise
Work With a Performance Audit Expert
Every audit is run by a senior performance engineer using Lighthouse, WebPageTest, Chrome DevTools, and CrUX field data side by side. You get root-cause analysis and a prioritized roadmap, not a generic score report.
1,500+
Optimization projects
100%
Core Web Vitals pass rate
90+
PageSpeed scores
Matt Suffoletto
Founder & CEO
Performance Audit Expert
Who This Is For
Is This Right for You?
E-Commerce Stores
Online stores where every 100ms of load time directly affects conversion rates, and where complex product pages, collection views, and checkout flows each present unique performance challenges.
Marketing Teams
Marketing teams running paid traffic to landing pages who need to know exactly why their pages are slow, and which fixes will have the biggest impact on conversion rates and quality scores.
Development Teams
Development teams that need expert-level performance analysis to guide their optimization work, with specific, actionable findings rather than generic tool recommendations.
Enterprise Organizations
Enterprise teams that need a formal performance audit document for stakeholders, procurement, or compliance, with executive summary, detailed findings, and measurable improvement projections.
Common Problems
What's Slowing You Down?
Unknown Performance Bottlenecks
You know your site is slow, but you don't know why. PageSpeed Insights gives you a score and generic recommendations, but doesn't tell you which specific resources, scripts, or rendering patterns are causing the problem. Without root-cause analysis, you're guessing at fixes.
Guide: Speed Testing ToolsConflicting Tool Recommendations
Lighthouse says one thing, GTmetrix says another, WebPageTest shows different results. Each tool measures differently, lab vs field, throttled vs unthrottled, different devices and locations. Without expert interpretation, you end up chasing contradictory recommendations.
Guide: Tool ComparisonNo Prioritization or Impact Ranking
Speed tools dump 30+ issues without ranking them. Your team wastes weeks fixing low-impact items while the real bottlenecks remain. A proper audit ranks every issue by score impact × effort × business value so you fix the right things first.
Guide: Core Web VitalsSurface-Level Analysis Misses Root Causes
Automated tools identify symptoms (large images, unused CSS) but miss root causes: render-blocking critical chains, excessive DOM complexity, layout thrashing, unoptimized font loading, and JavaScript execution bottlenecks that require waterfall and CPU profiling to diagnose.
Guide: Core Web VitalsLab Scores Don't Match Real User Experience
Your Lighthouse score is 90+ but real users complain about slowness. Lab tests measure one simulated visit; real users experience variability from different devices, networks, cached vs uncached visits, and third-party script timing. A proper audit bridges this gap.
Guide: Lab vs Field DataNo Baseline for Measuring Improvement
Without a comprehensive audit establishing baseline metrics across all page templates, you can't measure the impact of optimizations. You need before/after data across lab metrics, field data, and business KPIs to prove ROI.
Guide: Measuring PerformanceOur Solutions
How We Fix It
Multi-Layer Waterfall Analysis
We analyze the complete request waterfall for every key page template, identifying critical chains, render-blocking resources, connection timing, server response patterns, and resource loading order. This reveals exactly which requests are delaying your LCP and FCP.
JavaScript CPU Profiling
We profile main-thread JavaScript execution to identify long tasks, heavy event handlers, layout thrashing, forced reflows, and inefficient third-party scripts. This is the only way to find TBT and INP bottlenecks that waterfall analysis alone can't reveal.
Third-Party Script Impact Assessment
Every third-party script (analytics, ads, chat, social, A/B testing) is individually profiled for network cost, CPU time, main-thread blocking, and impact on Core Web Vitals. You see exactly what each script costs in milliseconds and score points.
Image & Asset Optimization Audit
Every image, font, CSS, and JavaScript file analyzed for format efficiency, compression, sizing, lazy-loading, preloading, and caching. We calculate the exact savings available from format conversion, responsive sizing, and delivery optimization.
Core Web Vitals Deep Dive
LCP, INP, and CLS analyzed individually with root-cause identification for each metric. We trace LCP to its exact resource and rendering chain, INP to its specific interaction handler, and CLS to its layout shift source, across both lab and field data.
Prioritized Action Plan with Loom Walkthrough
Every finding ranked by score impact × implementation effort × business value. High-impact, low-effort fixes come first. The plan includes a Loom video walkthrough where we explain every finding in plain English, no jargon, no confusion.
The Data
The Impact of a Faster Site
Proof
Our Results
Real engagements, real performance improvements, real revenue impact.
Therapevo
Audit identified 28 issues, all resolved. Lighthouse performance from 32 to 96, LCP from 8.4s to 1.6s, all Core Web Vitals passing in CrUX.
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Pure Parima
Audit revealed 3rd-party scripts consuming 2.8s of main-thread time. After remediation: mobile Lighthouse from 29 to 87, TBT from 2,800ms to 180ms.
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Platterful
Audit identified render-blocking Liquid, unoptimized images, and heavy app scripts. 80% load time reduction after implementing prioritized action plan.
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Our Process
How It Works
Data Collection & Baseline
We run comprehensive lab tests (Lighthouse, WebPageTest, Chrome DevTools) and pull real-user field data (CrUX, RUM) for every key page template, homepage, product/service pages, landing pages, blog posts, and category pages. Each page gets mobile and desktop testing across multiple locations. This establishes your complete performance baseline.
Deep Multi-Layer Analysis
We analyze every layer: server response timing (TTFB), request waterfall (critical chains, render-blocking resources), CPU profiling (main-thread tasks, long tasks, JS execution), rendering pipeline (layout, paint, composite), third-party script impact, image/asset efficiency, and caching configuration. Each layer gets its own section in the report.
Root Cause Identification
For every Core Web Vital metric, we trace to the root cause, not the symptom. LCP gets traced to its exact resource and rendering chain. INP gets traced to its specific JavaScript handler. CLS gets traced to its layout shift source element. This is the analysis that automated tools can't do.
Impact-Weighted Prioritization
Every finding is ranked by: (1) score impact, how many Lighthouse/CWV points it's worth, (2) implementation effort, hours to fix, (3) business value, traffic × conversion impact. High-impact, low-effort fixes go to the top. You get a clear, numbered action plan.
Report Delivery & Loom Walkthrough
You receive a detailed written report with all findings, data, and recommendations, plus a Loom video walkthrough where we explain every finding in plain English. We then schedule a live strategy session to discuss implementation priorities and answer questions.
Deliverables
What You'll Receive
Every engagement includes comprehensive documentation and reporting.
Comprehensive Audit Report
Detailed written report covering all 50+ metrics across server, rendering, JavaScript, images, third-party scripts, and Core Web Vitals, with screenshots, waterfall charts, and data tables.
Loom Video Walkthrough
A 20–45 minute video walking through every finding in plain English, showing exactly what's slow, why it's slow, and what to do about it. Shareable with your entire team.
Waterfall Analysis
Complete request waterfall for every key page template showing critical chains, render-blocking resources, connection timing, and resource loading order with annotated bottlenecks.
JavaScript CPU Profile
Main-thread execution timeline showing long tasks, heavy event handlers, layout thrashing, forced reflows, and third-party script CPU impact, with specific function-level attribution.
Third-Party Script Report
Every third-party script individually profiled for network cost, CPU time, main-thread blocking, and Core Web Vitals impact, with remove/defer/keep recommendations.
Image & Asset Audit
Every image analyzed for format, compression, sizing, lazy-loading, and preloading status. Every font, CSS, and JS file assessed for delivery efficiency. Includes calculated savings.
Core Web Vitals Root Cause Report
LCP, INP, and CLS individually traced to root causes with specific fix recommendations, not generic advice, but exact elements, resources, and code paths causing each issue.
Prioritized Action Plan
Numbered list of every fix ranked by score impact × effort × business value. Each item includes: what to fix, why it matters, expected improvement, and implementation guidance.
Competitor Speed Benchmark
How your performance compares against 3–5 direct competitors across Lighthouse scores, Core Web Vitals, and page weight, identifying competitive advantages and gaps.
Revenue Impact Projection
Custom report mapping your speed improvements to projected conversion gains, organic traffic improvements, and revenue impact based on your actual traffic and conversion data.
Caching & CDN Assessment
Complete review of browser caching, CDN configuration, edge caching, object caching, and page caching, with specific configuration recommendations.
Performance Baseline Document
Before-optimization baseline metrics for every page template, creating the measurement foundation to prove ROI after fixes are implemented.
Pricing
Transparent Speed Optimization Pricing
Get an instant estimate based on your site profile. No hidden fees, no lock-in contracts — just measurable speed improvements and revenue gains.
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Takes ~2 minutesWhat's your main goal?
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What We Handle
What A Full Performance Audit Covers
A complete audit covers Core Web Vitals, server response, render path, third-party scripts, caching, and competitor benchmarking.
Core Web Vitals Diagnosis
Analyze LCP, INP, and CLS in both lab and field data, identify the top-impact templates, and explain root causes per metric.
Server and TTFB Analysis
Measure server response under realistic conditions, identify slow queries, and recommend infrastructure or caching changes.
Render Path Analysis
Map render-blocking resources, critical CSS opportunities, and JavaScript execution cost across key templates.
Third-Party Script Audit
Inventory every external script with main-thread cost, network weight, and a defer, delay, facade, or remove recommendation.
Image and Asset Audit
Audit image weight, formats, dimensions, and lazy-load coverage. Recommend responsive sizing and next-gen format adoption.
Competitor Benchmark
Benchmark your performance against direct competitors so you know exactly how far ahead or behind you are.
FAQ
Frequently Asked Questions
Testimonials
What Audit Clients Say
"Platterful saw major improvements in site speed after working with Matt and the PageSpeed Matters team. They took our mobile score from the 50s to over 90 while keeping SEO intact. They were responsive, helpful, and continued to support us even after the project ended. Highly recommend."
Mobile score: 50s to 90+
Lowell
Co-Founder, Platterful
"Matt and the PageSpeed Matters team successfully helped us improve our page speed load times and get our core web vitals into the green."
Passed Core Web Vitals
Caleb Simonyi Gindele
Owner, Therapevo
"Couldn't be any happier with the work done by Matt and the PageSpeed Matters team, they were communicative, open, honest."
Mobile LCP 25.9s to 2.9s
Grace Smallman
Yakka Finance
Ready to Find Out What's Slowing You Down?
Order a full performance audit and get a prioritized roadmap of fixes with measurable revenue impact.
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