For Web Developers
See what your users actually experience, not just what your Lighthouse score says
Your Lighthouse score is 95, but users are complaining about slow performance. Sound familiar? VitalSentinel gives you real user monitoring data alongside synthetic testing, so you can see what's actually happening in production, catch regressions in real user data, and prove that your optimizations work. And because a release can break what crawlers see without slowing anything down, every page is also checked before and after JavaScript runs, and the pages you care about keep a history of exactly what changed.
Lab tests pass. Real users have a different experience
Lighthouse runs in an ideal environment. Your users don't. They're on slow networks, old devices, and across the world from your servers.
Lab testing shows perfect scores, but real users report completely different experiences
You can't reproduce the performance issues users are complaining about
It's impossible to tell if your optimizations actually made a difference in production
Performance regressions ship to production and go unnoticed for days or weeks
You don't know which specific pages, devices, or countries are having problems
Without production data, you're optimizing blind
A release quietly adds noindex or rewrites a canonical, and nobody notices until search traffic drops
Content that only renders with JavaScript looks fine in your browser, but crawlers get an empty page
What you get with VitalSentinel
Debug faster with production data
Stop trying to reproduce issues locally. See exactly what happened for the users who complained, with full device and network context.
Catch regressions in real user data
See when a deployment hurts performance in real user data. Roll back or ship a fix before it affects more users.
Prove your optimizations work
Show stakeholders real data proving that your performance work delivered measurable improvements in production, not just lab scores.
Prioritize with confidence
Focus optimization efforts on the pages, devices, and countries that actually matter for your users.
Catch the SEO regressions a release ships
Site Health Monitoring checks your pages around the clock, before and after JavaScript runs, and opens an issue when a problem spreads across pages: noindex added, page text missing from the HTML, broken menu and footer links, files failing to load.
Site Health MonitoringSee exactly what changed on a page
Page Monitoring records the HTML as served and the page after JavaScript on every check, so you can compare any two checks side by side. Titles, canonicals, structured data, response headers and time to first byte (TTFB) are all tracked.
Page MonitoringSee what your deploy did to Core Web Vitals
Compare Core Web Vitals before and after a release, straight from real users. Spot at a glance whether a deployment pushed LCP, INP, or CLS past acceptable levels – no need to reproduce it locally.
- Real user LCP, INP, and CLS from production
- Before and after comparison on every release
- Catch a bad change before it slips by unnoticed
Watch an LCP regression the moment it ships
A fresh bar lands as real user data streams in, so you see LCP climb right after a release instead of days later. Roll back or hotfix while it still affects only a fraction of users.
- Live real user LCP, updating continuously
- Regressions surface within minutes of a deploy
- Roll back before it reaches more users
Get alerted when a Core Web Vital crosses your threshold
Set thresholds for your Core Web Vitals and VitalSentinel alerts you when real user data crosses them. Drill into the exact device, page, or country behind the drop.
- Threshold alerts on Core Web Vitals
- Shows when your 75th percentile crossed the threshold
- Drill down by device, page, or country
Know when crawlers stop seeing what users see
Site Health Monitoring reads every page twice: the HTML your server sends, and the page after JavaScript runs. When text, links or a noindex exist in only one of them, or a change spreads across a section of the site, it opens an issue that shows the Google clicks at stake.
- Raw HTML and rendered page compared on every check
- Issues group the affected pages, so one bug is one issue
- "I've fixed it – check again" re-checks the pages on demand
A diff of what your deploy changed on the page
Watch the pages that matter in Page Monitoring and every check goes into that page's history. When something moves, you see the change in a plain sentence, then the before and after in the HTML source or the rendered page, with the time of the check that caught it.
- HTML source and After JavaScript views for every check
- Title, canonical, robots, structured data and headers tracked
- Custom CSS-selector elements for anything else on the page
A perfect lab score that hides a real problem
Scheduled Lighthouse tests give you a clean, repeatable lab score across Performance, Accessibility, Best Practices, and SEO. Set it next to real user monitoring and you can see exactly where a green lab result and a slow visitor part ways.
- Scheduled Lighthouse tests on every key page
- Performance, Accessibility, Best Practices, and SEO scores
- A repeatable lab baseline to compare against real users
Lab conditions look great. Pair this with real user data and you catch the gap between a passing test and what visitors actually experience.
Every module you need, in one place
Ten monitors and two analytics – on every plan, in a single dashboard.
RUM Monitoring
Track Core Web Vitals from real users
CrUX Monitoring
Chrome UX Report data from Google
Synthetic Monitoring
Automated Lighthouse testing
Site Health Monitoring
A technical SEO crawl that never stops
Page Monitoring
Catch SEO changes on your key pages
Indexing Monitoring
Google indexing status
Robots.txt Monitoring
Track robots.txt changes
Sitemap Monitoring
Every URL added to or removed from sitemaps
Server Log Monitoring
What Googlebot and AI crawlers request
Uptime Monitoring
24/7 availability tracking
How developers use VitalSentinel
Add the RUM script
A single lightweight script (~13KB) captures Core Web Vitals from real users. Works with any framework. Takes minutes to integrate.
Set up synthetic monitoring
Configure scheduled Lighthouse tests for your key pages. Choose the test frequency and locations. Results are stored automatically.
Set performance thresholds
Define acceptable ranges for Core Web Vitals. Get alerts when metrics exceed thresholds so you can catch regressions quickly.
Debug with real data
When issues arise, drill down by device, browser, country, or page. Server Log Monitoring adds the other side: the status codes and response times your server gave Googlebot and AI crawlers.
Every module included. You only choose your coverage
All plans include all twelve modules. Start free, upgrade only when you need wider coverage.
Starter
For small businesses and personal projects
- 3 domains
- 100K RUM page views/mo
- 1M analytics events/mo
- 2,500 API credits/mo
Lite
For consultants and growing businesses
- 5 domains
- 250K RUM page views/mo
- 5M analytics events/mo
- 25,000 API credits/mo
Stop guessing. Start measuring.
Get production performance data alongside lab testing. Debug faster, ship with confidence.