PerfKit
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Analyze Web
Performance

Enter any URL to find what's slowing it down — blocking scripts, heavy bundles, unoptimized assets, and Core Web Vitals issues.

Core Web Vitals
Bundle Analysis
Third-Party Audit
CORE WEB VITALS
LCP
2.9s
INP
263ms
CLS
0.04
BLOCKING RESOURCES
Google Tag Manager
320ms
Third-party scripts
1.2s
BUNDLE ANALYSIS
Unused JavaScript
450 KB
Render-blocking CSS
84 KB
Uncompressed images
1.8 MB

Tools

View all 13 tools

FIELD DATA

2/2

Chrome User Experience Report

Analyze historical performance data based on real users across the globe. Essential for understanding SEO and search rankings.

Comparative Analysis

Benchmark up to 5 URLs side-by-side to track regressions or validate performance fixes.

LAB ANALYSIS

3/3

Automated Lighthouse Audits

Full Lighthouse audit with performance, accessibility, best practices, and SEO scores.

Execution Profiler

Deep-dive into main thread activity. Diagnose long tasks, JavaScript execution times, and layout shifts.

Stack Inspection

Identify underlying technologies, frameworks, and CMS platforms to understand their impact on total page weight.

SERVER ANALYSIS

1/5

Page Weight Analyzer

Measure the resource weight of any page — JS, CSS, images, and fonts with per-file breakdown.

Soon

HTTP Header Audit

Analyze caching, compression, CDN, and security headers for performance issues.

Soon

Redirect Profiler

Trace the full redirect chain with per-hop timing and protocol analysis.

Soon

Image Analyzer

Detect oversized, unoptimized, and improperly loaded images with fix suggestions.

Soon

Third-Party Impact

Classify and measure the performance cost of every third-party script.

MONITORING

0/3
Soon

Performance Budgets

Set metric thresholds and track field data against your budgets over time.

Soon

Regression Detector

Automatically detect statistically significant regressions in CrUX trends.

Soon

Scheduled Audits

Run recurring analysis on your URLs with historical tracking and alerts.

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