Automated Lighthouse audits and Core Web Vitals tracking for every page. Detect performance regressions instantly and keep your website fast 24/7.
Page speed monitoring - also called website performance monitoring, web page speed testing, or Lighthouse monitoring - is the continuous, automated measurement of how fast your web pages load and render for real users. Unlike basic uptime monitoring, which only checks whether a server responds, page speed monitoring uses tools like Google Lighthouse and PageSpeed Insights to run full performance audits that evaluate rendering speed, visual stability, interactivity, and overall page quality.
In a world where Google uses Core Web Vitals as a search ranking factor and where users expect pages to load in under three seconds, page speed is no longer a nice-to-have metric - it directly affects your SEO rankings, bounce rate, conversion rate, and revenue. Even a one-second increase in page load time can reduce conversions by up to 7%, according to industry studies. Monitoring page speed continuously ensures you catch regressions the moment they happen, not when your traffic or revenue drops weeks later.
UptimeMonitorX's built-in page speed monitoring runs automated Google Lighthouse audits against the PageSpeed Insights API at regular intervals. Each audit records a full set of performance metrics - Performance score, Accessibility score, Best Practices score, SEO score, and all Core Web Vitals (LCP, CLS, TBT, FCP). If the performance score falls below your configured threshold, UptimeMonitorX treats it like a downtime event and sends you instant alerts through Email, Slack, Telegram, Discord, or WhatsApp. Setup takes 30 seconds, and the free plan includes full access to this feature.
Run Google Lighthouse performance audits automatically at regular intervals. UptimeMonitorX triggers real Lighthouse tests via the Google PageSpeed Insights API and records Performance, Accessibility, Best Practices, and SEO scores for every check - no manual effort required.
Monitor all Core Web Vitals that Google uses for search rankings: Largest Contentful Paint (LCP), Cumulative Layout Shift (CLS), Total Blocking Time (TBT), and First Contentful Paint (FCP). Visualise each metric with colour-coded progress bars so you can spot regressions instantly.
Set a minimum Lighthouse performance score (1-100) for each monitor. When the score drops below your threshold, UptimeMonitorX marks the monitor as down and triggers instant alerts - just like a traditional uptime check, but for page speed.
Receive real-time notifications via 17+ channels including Email, Slack, Discord, Telegram, MS Teams, PagerDuty & more the moment your page speed score falls below the threshold. Get recovery alerts when performance improves, so you always know the current state of your site speed.
Track page speed scores and Core Web Vitals over time with interactive analytics charts. Identify gradual performance degradation, correlate slowdowns with deployments, and prove improvement after optimisation work with hard data.
Lighthouse audits run with the mobile strategy by default - the same strategy Google uses for mobile-first indexing. This ensures your page speed monitoring reflects the experience real users have on mobile devices, the majority of web traffic today.
Beyond raw performance, each audit also captures Accessibility, Best Practices, and SEO scores. See all four Lighthouse categories in a single dashboard widget, so you can track overall page quality alongside speed.
Trigger performance audits from monitoring nodes across North America, Europe, South America, and Asia-Pacific. Understand how page speed varies by geography and ensure fast load times for your global audience.
Add your page URL - Enter the URL you want to monitor, select the "Lighthouse" monitor type, and set your minimum acceptable performance score (default is 80). The entire setup takes under 30 seconds.
Automated Lighthouse audits - At every check interval, UptimeMonitorX calls the Google PageSpeed Insights API to run a full Lighthouse audit on your page. The audit returns Performance, Accessibility, Best Practices, and SEO scores, plus Core Web Vitals: LCP, CLS, TBT, and FCP.
Threshold-based alerting - If the Lighthouse performance score drops below your threshold, UptimeMonitorX immediately sends alerts through your configured channels - Email, Slack, Telegram, Discord, or WhatsApp. When the score recovers above the threshold, you receive a recovery notification.
Analyse trends and optimise - View historical performance score graphs, Core Web Vitals trends, and per-audit breakdowns in the Lighthouse Analytics dashboard. Correlate performance changes with deployments, third-party script additions, or infrastructure changes to pinpoint the root cause of slowdowns.
Core Web Vitals are a set of real-world, user-centred metrics defined by Google that measure the loading performance, visual stability, and interactivity of a web page. Since 2021, these metrics are part of Google's Page Experience ranking signals, meaning they directly influence your position in search results.
Good: < 2.5s · Needs Improvement: < 4.0s · Poor: ≥ 4.0s
Measures how long it takes for the largest visible content element (image, video, or text block) to render. LCP reflects perceived loading speed - the moment a user feels the page has "loaded."
Good: < 0.1 · Needs Improvement: < 0.25 · Poor: ≥ 0.25
Quantifies unexpected visual shifts during page load. High CLS means elements jump around as the page renders, causing users to accidentally click wrong links or lose their reading position.
Good: < 200ms · Needs Improvement: < 600ms · Poor: ≥ 600ms
Measures the total time the main thread was blocked for long enough to prevent input responsiveness. TBT is the lab equivalent of First Input Delay (FID) and directly correlates with how "janky" a page feels.
Good: < 1.8s · Needs Improvement: < 3.0s · Poor: ≥ 3.0s
Marks the time from navigation to when the browser first renders any content (text, image, SVG, or canvas). FCP tells you when users first see something on the screen, giving feedback that the page is actually loading.
Page speed monitoring is the practice of continuously measuring how fast your web pages load and render for visitors. It uses automated tools like Google Lighthouse to audit page performance at regular intervals, tracking metrics such as Largest Contentful Paint (LCP), Cumulative Layout Shift (CLS), Total Blocking Time (TBT), and First Contentful Paint (FCP). When performance drops below an acceptable threshold, the monitoring system alerts you so you can fix the issue before it impacts users, SEO, or revenue.
Uptime monitoring checks whether your website is reachable - does it return a 200 OK? Page speed monitoring goes deeper: it measures how fast the page loads and renders. A site can be technically "up" but painfully slow, leading to high bounce rates and poor search rankings. UptimeMonitorX treats page speed monitoring as a first-class monitor type - if the Lighthouse performance score drops below your threshold, it triggers the same alert pipeline as a full outage.
Yes. UptimeMonitorX includes page speed monitoring (Lighthouse audits) on all plans, including the free tier. Create a performance monitor, set your target threshold, and start tracking Core Web Vitals immediately - no credit card or API keys required.
Lighthouse audits run at the same interval as your other monitors - every 5 minutes on the free plan, or as frequently as every 60 seconds on paid plans. Because each audit calls the Google PageSpeed Insights API (which can take 15-60 seconds), performance monitors use a minimum 60-second timeout to ensure accurate results.
UptimeMonitorX tracks Largest Contentful Paint (LCP), Cumulative Layout Shift (CLS), Total Blocking Time (TBT), and First Contentful Paint (FCP). Each metric is colour-coded against Google's recommended thresholds: green for good, yellow for needs improvement, and red for poor. These are the same metrics Google uses to evaluate page experience for search ranking purposes.
No. UptimeMonitorX uses the Google PageSpeed Insights API, which runs the Lighthouse audit on Google's own infrastructure - not on your server. Your website receives a single page request per audit, identical to a normal visitor. There is no additional load, no JavaScript injected, and no impact on your real users.
Yes. Each page speed monitor is an independent monitor with its own URL and performance threshold. You can create one monitor for your homepage with a threshold of 90, another for your blog with a threshold of 75, and a third for your checkout page with a threshold of 85 - each with its own alert settings.
Google uses Core Web Vitals (LCP, CLS, and related metrics) as a ranking factor in its search algorithm. Pages that load slowly, shift layout unexpectedly, or block interaction are penalised in search results relative to faster competitors. Monitoring page speed continuously ensures you catch and fix regressions before they affect your search rankings, organic traffic, and ultimately, revenue.
Set up your first Lighthouse performance monitor in 30 seconds. Free plan includes full Core Web Vitals tracking - no credit card required.
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