Lighthouse Report Viewer
Upload a Lighthouse JSON report to explore scores, metrics, and audits interactively.
Drop your Lighthouse JSON here
or click to browse files
How to export Lighthouse JSON:
- Open Chrome DevTools (F12)
- Go to the Lighthouse tab
- Run an audit
- Click "Export" → "Save as JSON"
How to Read a Lighthouse Report
Lighthouse audits your page across five categories. Each category receives a score from 0-100, with 90+ being good, 50-89 needing improvement, and below 50 being poor.
Focus on Performance first—it directly impacts user experience and SEO. Within Performance, prioritize the Opportunities section, which shows specific improvements with estimated savings.
Category Quick Reference
Performance
Loading speed, interactivity, visual stability
Accessibility
Screen readers, contrast, keyboard navigation
Best Practices
Security, modern APIs, image optimization
SEO
Meta tags, crawlability, mobile-friendliness
PWA
Installability, offline support, app-like experience
Pro Tips for Improving Your Score
Start with Quick Wins
Focus on opportunities with the highest estimated savings first. Image optimization and unused code are often easy fixes.
Test Multiple Times
Lighthouse scores can vary between runs. Test 3-5 times and average the results for a more accurate picture.
Prioritize Core Web Vitals
LCP, CLS, and INP directly affect search rankings. Focus on getting these green before other optimizations.
Test on Mobile
Google uses mobile-first indexing. Your mobile score matters more than desktop for SEO.
Check Field Data
Lab data (Lighthouse) is synthetic. Check Chrome UX Report for real-world user experience data.
Don't Chase 100
Diminishing returns after 90. A score of 90+ is excellent—spend time on features, not micro-optimizations.
01How do I view a Lighthouse JSON report?
Upload your Lighthouse JSON file by dragging and dropping it onto this page, clicking the upload area, or pasting the JSON content directly. The viewer will parse and display your performance scores, metrics, and audit results in an interactive format.
02How do I export a Lighthouse report as JSON?
In Chrome DevTools, run a Lighthouse audit then click "Save as JSON" in the report header. From the command line, run: npx lighthouse <url> --output=json --output-path=report.json. The PageSpeed Insights API also returns JSON that works with this viewer.
03What information does a Lighthouse JSON report contain?
Lighthouse reports include performance scores (0-100), Core Web Vitals metrics (LCP, CLS, TBT), detailed audit results for performance, accessibility, best practices, SEO, and PWA categories, plus timing data, screenshots, and optimization opportunities.
04Can I compare multiple Lighthouse reports?
This viewer shows one report at a time. For comparing reports over time, consider Lighthouse CI which stores historical data, or export multiple JSON reports and compare the metrics manually. The Unlighthouse CLI can scan your entire site and track changes.
05Why use a Lighthouse report viewer instead of the HTML report?
JSON reports are smaller, easier to store, and work better with automation. This viewer provides the same visual experience as HTML reports, with additional features like dark mode, better mobile support, and the ability to quickly inspect specific audits.
Explore more Lighthouse tools