Free PageSpeed
& Core Web Vitals Audit
Real Lighthouse audit on any URL. Get Performance, Accessibility, SEO, and Best Practices scores plus full Core Web Vitals (LCP, FCP, CLS, INP) in seconds.
Know why your page is slow before it costs you.
Paste any URL and get a real Google Lighthouse audit: a 0 to 100 performance score, full Core Web Vitals, and the exact fixes that move them, in about 20 seconds.
You know the page is slow. You just can't see why.
Every extra second of load sheds visitors and hands the ranking to a faster rival, most of all on a phone. But "it feels slow" is not a fix. You need the one metric that is failing and the thing that is causing it, and that is exactly what a Lighthouse audit gives you.
One URL in. A full report out.
Paste a URL
Any page, mobile or desktop. No signup, no setup, no code to install.
Google runs Lighthouse
We call Google's official PageSpeed Insights API, which runs a real Lighthouse audit in a Google data center. It takes about 15 to 30 seconds.
You get the fixes
Four scores, full Core Web Vitals judged against Google's thresholds, and a ranked list of the changes that will help most.
What these terms mean
Lighthouse
Google's open audit engine. It loads your page in a controlled test and grades how fast, stable, and responsive it is.
The engine behind PageSpeed InsightsPerformance score
A single 0 to 100 grade for speed, built from your load metrics. Higher is faster. 90 and up is the green band.
58 means there is real work to doLCP
Largest Contentful Paint. How long the biggest thing on screen, usually a hero image or heading, takes to appear. Good is under 2.5 seconds.
3.8s means the main content is lateINP
Interaction to Next Paint. How quickly the page reacts when you tap or click. Good is under 200 milliseconds.
240ms feels a touch sluggishCLS
Cumulative Layout Shift. How much the page jumps around while it loads. Lower is steadier. Good is under 0.1.
0.02 is rock solidLab vs field data
This report is a lab test: one load, one place, one set connection. Field data is what real visitors see over time. Google ranks on field data, so treat the score as a diagnostic.
Great for finding the fix, not the exact rankingNot just speed. The whole health of the page.
Every audit returns four Lighthouse scores at once, each from 0 to 100: Performance, Accessibility, Best Practices, and SEO. One run tells you where the page is strong and where it is quietly leaking.
- Performance, Accessibility, Best Practices, and SEO together
- Every score color coded to Google's own bands
- Switch between mobile and desktop and re-audit either
Rule of thumb: 90 to 100 is good, 50 to 89 needs improvement, and 0 to 49 is poor. Start with whichever score sits lowest.
The three metrics Google actually watches.
LCP, INP, and CLS are Google's Core Web Vitals, the signals it folds into ranking. The audit measures each one and marks it good, needs work, or poor against Google's published thresholds, so you see the exact line you are on.
- LCP, INP, and CLS with each one graded against its threshold
- FCP, TBT, and Speed Index fill in the rest of the load
- Color tells you at a glance which vital is dragging the score
Why it works: the thresholds are Google's own. Good is LCP under 2.5s, INP under 200ms, and CLS under 0.1. Clear all three and the page passes.
It doesn't just score. It tells you what to fix.
Below the metrics, the report lists opportunities, each with the time it could save, ranked so the biggest win is at the top. Under them, diagnostics explain the deeper causes. You get a to-do list, not just a grade.
- Opportunities ranked by estimated time saved
- Plain-language titles like "properly size images"
- Diagnostics that point to the root cause behind each metric
Pro tip: fix from the top down. The first one or two items usually recover most of the score for the least work.
Top opportunities · yoursite.com
Everything else the audit hands you.
Mobile and desktop
Audit either profile. Test the phone view first, since that is where most visitors and Google's index look.
Savings estimates
Each opportunity shows the time it could shave off the load, so you can weigh effort against payoff.
Diagnostics
The deeper technical findings behind the metrics, from oversized payloads to heavy main-thread work.
Accessibility checks
Contrast, labels, and alt text roll into the Accessibility score, so a fast page is also a usable one.
SEO basics
The SEO score flags crawlability and mobile-friendliness gaps that can quietly hold a page back in search.
Re-run anytime
Free, no signup, no limit. Re-audit after each release so a new script or image does not slow the page back down.
How to turn a result into a fix.
A report is only useful if you know which line to act on. Here is the exact read on our example run, yoursite.com on mobile, the way an experienced developer would think it through.
From a slow page to a clear plan.
Know if speed is costing you
See in seconds whether your page is fast enough to keep visitors and rank, with a clear score and the first thing to fix.
Find the real bottleneck
Get the exact failing metric and the items causing it, from a blocking script to an oversized image, and fix the cause instead of guessing.
Protect the conversions you paid for
Slow pages quietly lose the visitors your campaigns bring in. Check the pages that matter and stop speed from eating your rate.
Audit a client page on the spot
Paste a URL and show the score, the failing vitals, and the top fixes in one screen, before you scope or pitch the work.
Questions, answered.
Yes. We call Google's official PageSpeed Insights API, which runs a real Lighthouse audit in a Google data center. You get the same lab measurements PageSpeed Insights reports, not an estimate of our own.
Not exactly, and that is worth knowing. This is a lab run: one load, one place, one connection. Google's ranking signal comes from real-user field data, the Chrome UX Report, gathered over time. So treat this score as a diagnostic that tells you what to fix, not as your precise ranking input.
It defaults to mobile, because that is where most visitors are and what Google indexes with. You can switch to desktop and re-audit the same URL in a click.
Google treats 90 to 100 as good, 50 to 89 as needs improvement, and 0 to 49 as poor. For Core Web Vitals, aim for LCP under 2.5 seconds, INP under 200 milliseconds, and CLS under 0.1.
A lab run varies a little each time with network and server conditions, so a few points of swing is normal. Do not chase the exact number. Look at which metric is failing and what the opportunities say is causing it, because that is where the real fix lives.
Yes. Paste your URL and read the top of the list. The scores are color coded, the failing vital is marked, and each fix is written in plain language, so you know what to hand your developer or your site builder.
Paste a URL and see what's slowing it down.
It takes one link. You'll get a real Lighthouse score, full Core Web Vitals, and the ranked list of fixes, in about 20 seconds. Free, and no signup.
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