Free Tool · Lighthouse Score Calculator
How Google Scores Your Site
The Lighthouse performance score behind PageSpeed Insights is not a mystery. It is five measurements, each graded on a published curve, each carrying a published weight. The sliders start at the median page on the web, which scores exactly 50. Move them and watch exactly where every point comes from.
Google scores your site on its mobile experience first. The same numbers score differently on the desktop curves. Flip the toggle and watch the curve move.
Mobile Score
Where the points come from
Largest Contentful Paint scoring curve, mobile. Select any metric above to inspect its curve.
The curve is log-normal: the first improvements earn the most points, and the returns shrink as you approach the top. That is why going from 60 to 80 is easier than going from 80 to 95.
This is the lab model with your hands on the dials. Your real page has real numbers. Run the free audit and see them.
Run Your Free AuditCurves, weights, and control points read from the Lighthouse source, version 13.4.1, retrieved 2026-08-25. This tool models the published lab scoring math and is not affiliated with Google.
Scores Tell You Where You Stand. Audits Tell You What to Do.
The calculator above models exactly what PageSpeed Insights measures: the lab performance of a single page. That is one dimension of one page. Modern visibility is decided across four, on every page you have. Here is how the tools compare.
Google PageSpeed Insights
Free
- Tests one page at a time.
- Performance only: the five lab metrics you just explored, plus real-user field data where Google has it.
- Gives you the score. What to do about it, and what it means for your business, is left to you.
A great instrument. Also where most analysis stops.
Xavarro Free Website Intelligence Audit
Free, about 30 seconds
- Four pillars, not one: SEO, AI search visibility, accessibility, and performance.
- Performance runs on the same PageSpeed data, scored on both the mobile and desktop models.
- Category breakdowns and an overall grade, so you can see where the points are actually lost.
The starting point. No account, no sales call, no strings.
Deep Forensic Audit
The full picture
- Crawls your whole site, page by page, not a single URL.
- Findings tied to the specific elements causing them, prioritized by impact and effort.
- Competitor comparison and your business context folded in, and every report is reviewed by us before it reaches you.
Built for owners who want a working plan, not another score.
The free audit takes 30 seconds and answers where you stand. When you are ready to know exactly what to fix, in what order, and what it is worth, that is a conversation, not a checkout page.
Ask Us About the Deep Forensic AuditMore free tools from Xavarro
See all free toolsWebsite Intelligence Audit
Free, about 30 seconds
Score any website across four pillars: SEO, AI search visibility, accessibility, and performance. Category breakdowns, an overall grade, and mobile versus desktop performance.
AI Search Visibility Check
Free, instant
Check whether your website blocks AI search crawlers and assistants like GPTBot, ClaudeBot, and PerplexityBot. Know if AI tools can even see your site.