Track Lighthouse scores run after run.
PageSpeed monitors run Google Lighthouse against your pages on a schedule and keep the scores. When a deploy quietly doubles your load time, the chart says so the same day, not at the next quarterly audit.
Track all 4 Lighthouse scores instead of sampling them.
Every run records performance, accessibility, best practices and SEO, each scored 0 to 100. Green from 90 up, orange from 50 to 89, red below that, the same bands Lighthouse uses everywhere.
A one-off audit describes a single afternoon. A monitor turns the same audit into a series, and the series is what tells you whether things are drifting.
- Performance, accessibility, best practices and SEO
- Scored 0 to 100 on every run
- History kept per monitor
Capture Core Web Vitals from every single run.
Each audit records Largest Contentful Paint, First Contentful Paint, Cumulative Layout Shift, Total Blocking Time and Speed Index, the metrics Google uses as ranking signals.
The targets are documented and unambiguous: LCP under 2.5 seconds, FCP under 1.8, CLS under 0.1, TBT under 200 milliseconds, Speed Index under 3.4 seconds. The monitor shows where you stand against each.
- 5 metrics recorded per audit
- Documented targets shown against each metric
Measure desktop and mobile separately.
Each monitor audits as desktop or as mobile. Mobile runs on a simulated mid-range device over a slower network, so its scores run lower, and that lower number is what most of your visitors experience.
Create one monitor per strategy on the same URL and the gap between the two becomes a number you can watch instead of a surprise in Search Console.
- Desktop or mobile per monitor
- Two monitors cover both views of one URL
For pages where speed pays the bills.
Ecommerce teams
Slow product pages lose buyers before the add-to-cart button renders. A scheduled audit catches the regression the day the oversized hero image ships.
SEO-focused sites
Performance is a ranking signal, and rankings move slowly enough that you want the early warning. The score moves 3 weeks before the traffic graph does.
Marketing sites after launch
Launch week gets the performance pass. Then someone embeds a video, adds a chat widget and installs one more tag. The monitor is how the launch-day speed survives the year.
See what it covers and what it doesn't.
Covered
- Scheduled Lighthouse audits through Google's PageSpeed Insights API
- Performance, accessibility, best practices and SEO scores
- LCP, FCP, CLS, TBT and Speed Index per run
- Desktop or mobile audit strategy per monitor
- Score history and trends per page
- Alerts on 13 notification channels
Out of scope
- Real-user monitoring: Lighthouse is lab data, it complements field data rather than replacing it
- Private pages: Google's API audits the URL, so it must be publicly reachable
- Request-level profiling: for waterfalls and flame charts, use your browser's devtools
For the technically curious.
Google's API on your schedule
Each check calls the PageSpeed Insights v5 API with all 4 Lighthouse categories. The audit itself runs on Google's infrastructure, in a consistent environment your laptop can't replicate.
The one check that leaves home
Every other Checkmate monitor runs from your instance. PageSpeed is the exception, because a Lighthouse audit needs a real browser environment, and Google operates it.
Bring an API key
Audits work without one, but Google throttles anonymous use. Add a free API key under Settings to raise the rate limits for steady schedules.
Quota-aware intervals
Intervals range from seconds up to 30 minutes, and every run spends API quota. Pick the longest interval that still gives you the cadence you need.
Frequently asked questions
PageSpeed monitoring runs Google Lighthouse against a URL on a schedule and records the results. Checkmate keeps the 4 Lighthouse scores plus Core Web Vitals per run, so performance changes show up as a trend.
The 4 Lighthouse category scores (performance, accessibility, best practices, SEO) and 5 Core Web Vitals: Largest Contentful Paint, First Contentful Paint, Cumulative Layout Shift, Total Blocking Time and Speed Index.
Checks work without one, but Google throttles anonymous requests. A free PageSpeed Insights API key, added in Settings, raises the limits enough for regular schedules.
Both, ideally as two monitors on the same URL. Mobile audits simulate a mid-range phone on a slower network, which is closer to what most visitors experience, while desktop tracks your best case.
No. The audit runs through Google's PageSpeed Insights API, which must be able to reach the URL publicly. For availability of private pages, use an HTTP monitor instead.
Checkmate is one. It is open source under AGPL-3.0 and self-hosted, so scheduled Lighthouse audits cost you nothing beyond your own server.
