LCP Diagnostics
Identify the exact elements dragging down your Largest Contentful Paint metric.
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Analyze Your Site Page Speed
Run a fast, comprehensive page speed audit to uncover slow pages, prioritize fixes, and improve Core Web Vitals for better SEO and UX.
Analysis report
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Powering 145,000+ Performance Audits Worldwide
Join thousands of developers and marketers optimizing their page load speeds.
1.5M+
Pages Analyzed
Monthly
850K+
Bottlenecks Fixed
Last 30 Days
58 %
Avg Speed Boost
Post-Optimization
99 %
Accuracy
In LCP Tracking
Make smarter decisions
Master Your Core Web Vitals
Stop losing rankings and customers due to slow-loading pages. PageSpeed Pro instantly analyzes your site to identify render-blocking resources, large payloads, and scripting bottlenecks.
- Analyze Largest Contentful Paint (LCP)
- Assess Cumulative Layout Shift (CLS)
- Find unoptimized images and CSS
- Discover JavaScript execution delays
Features
Complete Performance Suite
Everything you need to debug, optimize, and accelerate your site.
Payload Analysis
Measure and break down your page weight by scripts, stylesheets, and media.
JavaScript Execution
Find long-running tasks and scripts that block main thread responsiveness.
Visual Stability (CLS)
Track exactly which DOM elements are shifting during page load.
Server Response Time
Measure TTFB and discover backend delays holding your frontend back.
Image Opportunities
Highlight oversized images and formats that need next-gen conversion.
Competitive Benchmarking
Compare your load times against your top competitors in real-time.
Export Developer Audits
Download comprehensive technical CSV reports for your engineering team.
How it works
Analyze Speed in 3 Steps
Find exact performance bottlenecks without manual dev tools.
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1
Enter Your URL
Provide the page URL you want to test. Our engine fetches elements just like a real mobile or desktop browser.
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2
Run the Audit
We analyze CSS payloads, script execution time, image optimization, TTFB, and layout shifts automatically.
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3
Execute Fixes
Receive a developer-ready report outlining exact scripts to defer, images to compress, and CSS to inline.
Why choose
Why Choose PageSpeed Pro
Actionable diagnostics that go beyond generic speed scores.
Core Web Vitals Focus
Stop guessing. Identify exact elements impacting Largest Contentful Paint, Interaction to Next Paint, and Cumulative Layout Shift.
DOM & Script Profiling
Find long tasks blocking the main thread, excessive DOM depths, and overly complex CSS selectors that slow rendering algorithms.
Real Chrome Emulation
Audits run via headless Chrome instance simulating proper viewport, user agents, and constrained network/CPU profiles.
Historical Diagnostics
Track your score over time and correlate drops in performance with your recent deployments or dependency upgrades.
Regression Alerts
Receive immediate alerts to webhooks or Slack when a new code release increases your load average beyond a threshold.
Actionable Directives
Receive clear "to-do" lists like "defer script X", "compress image Y", and "inline CSS block Z" rather than vague metrics.
Who it's for
Who Needs PageSpeed Pro?
Performance matters for conversions, rankings, and user retention.
Frontend Developers
Pinpoint exactly which React component, unoptimized image bundle, or third-party ad script is locking up the browser thread.
- Debug long JavaScript tasks
- Optimize Critical Render Path
- Resolve dependency bloat
E-Commerce Brands
Every second delay costs conversion. Optimize heavy category pages, product galleries, and checkout flows to ensure seamless buying.
- Improve checkout fluidity
- Optimize hero image loading
- Lazy-load offscreen products
SEO Professionals
Core Web Vitals are a direct ranking factor. Ensure technical hurdles aren't preventing your high-quality content from ranking #1.
- Pass Core Web vitals
- Identify server response latency
- Generate technical audit reports
DevOps Engineers
Understand how infrastructure response times (TTFB) and CDN cache hit rates influence end-user experienced load speeds globally.
- Measure Time to First Byte
- Verify CDN asset delivery
- Locate network bottlenecks
Testimonials
Success Stories
How developers are saving milliseconds with PageSpeed Pro
★★★★★
PageSpeed Pro showed us exactly which third-party scripts were blocking our main thread. We deferred them and dropped our LCP from 4.2s to 1.8s.
Verified User
★★★★★
The payload analysis is incredible. We discovered our images weren't properly compressed in next-gen formats. Converting them saved us 2MB per page load.
Verified User
★★★★★
We use PageSpeed Pro for all our client audits. The granular breakdown of layout shifts (CLS) makes it trivial to stabilize the UI.
Verified User
★★★★★
The visual stability tracking warned us about ad injection shifts. We defined container sizes and eliminated our CLS penalty instantly.
Verified User
★★★★★
TTFB insights revealed our database queries were holding back our initial response. A quick caching layer fix drastically improved load times.
Verified User
★★★★★
Seeing how we compare to competitors' load times pushed our team. We now ship smaller bundles and consistently out-load our top 3 rivals.
Verified User
FAQ
Frequently Asked Questions
Understanding Page Speed & Core Web Vitals
What is a Page Speed Analyzer?
A Page Speed Analyzer is a diagnostic tool that measures how quickly your website's elements load in a browser. It dissects the network waterfall, execution time, and render path to pinpoint bottlenecks preventing your site from feeling entirely instant.
What are Core Web Vitals?
Core Web Vitals are specific factors Google considers important in a webpage's overall user experience. They primarily consist of Largest Contentful Paint (LCP, regarding loading performance), Interaction to Next Paint (INP, regarding responsiveness), and Cumulative Layout Shift (CLS, regarding visual stability).
How does page speed affect SEO?
Page speed is a confirmed ranking factor for both mobile and desktop searches. Sites that pass Core Web Vitals assessments receive a slight ranking boost, while very slow sites may be penalized in search results.
What is "render-blocking" CSS/JS?
Render-blocking resources are scripts and stylesheets that must be downloaded, parsed, and executed before the browser can render anything to the screen. To fix this, you should inline critical CSS and defer non-critical Javascript execution.
How can I fix a poor Largest Contentful Paint (LCP) score?
A poor LCP usually happens because the largest element (often a hero image or text block) loads slowly. You can fix this by compressing images, ensuring your server responds quickly (TTFB), using a CDN, and preventing render-blocking CSS/JS from delaying the render.
How often should I run audits?
You should run automated audits whenever pushing new code to a staging environment (using CI/CD pipelines). Additionally, reviewing overall site performance monthly ensures creeping unoptimized imagery or large script dependencies don't slowly negatively impact your Core Web Vitals.
Ready to Accelerate Your Pages?
Start your free Page Speed analysis now and eliminate those long load times.
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