Website Monitoring Tools: What to Watch and Which to Pick
Website monitoring tools compared: what to watch beyond uptime, and how UptimeRobot, Better Stack, Pingdom, StatusCake and Uptime Kuma differ.
If you look after one site, "monitoring" means getting an email when it goes down. If you look after 30 client sites, it means knowing which site, which problem, who should hear about it, and whether the client ever finds out you caught it.
This guide covers what to monitor, the four types of tools, an honest comparison of the well-known ones (with their pricing as of October 2026), and what changes when the sites belong to your clients. It works for any platform: WordPress, Webflow, Shopify, or a framework on Vercel.
What Should Website Monitoring Check?
Uptime is the start, not the whole list. These are the failures that actually take clients' sites off the internet or damage them quietly.
| What to monitor | What goes wrong | Why uptime alone misses it |
|---|---|---|
| Uptime | Server down, bad deploy, host outage | This is the one it catches |
| SSL certificate expiry | Certificate lapses, browsers show a full-page warning | The server is "up" but nobody can get in |
| Domain expiry | Registration lapses and the site disappears | DNS stops resolving, often on a date nobody tracked |
| DNS changes | Records altered or deleted, email breaks | The site may still load while email fails |
| Blocklist and malware listings | Site flagged by search engines or browsers | The page loads fine for you |
| Speed and Core Web Vitals | Pages slow down after an update or a new script | Slow is still up |
| Broken pages and key flows | A form, checkout, or key page returns an error | The homepage still returns 200 |
On speed, use Google's thresholds: Largest Contentful Paint of 2.5 seconds or less, Interaction to Next Paint of 200 milliseconds or less, and Cumulative Layout Shift of 0.1 or less, measured at the 75th percentile of real page loads.
Domain and certificate expiry are the cheapest failures to prevent and the most embarrassing to explain. Put the dates in a system that warns you 30 and 7 days ahead.
Types of Website Monitoring Tools
Most tools fit one of four types, and many sites need more than one.
- Standalone uptime monitors. They request your URL every minute or few minutes from outside and alert you when it fails. Cheap, simple, and the right starting point.
- Synthetic monitoring. Scripted checks that behave like a visitor: log in, add to cart, submit a form. Use them for the flows that make money.
- Real user monitoring (RUM). A script on the site records how real visitors experience speed and errors. It tells you what lab tests cannot, but it needs traffic and installs code on the site.
- All-in-one platforms. Monitoring sits next to hosting, domains, billing, or client reporting. You trade some depth in each check for seeing everything in one place.
None of these is "best." A single store with real revenue may need synthetic checks and RUM. A studio with 30 brochure sites needs broad coverage and reports more than scripted checkout tests.
Website Monitoring Tools Compared (October 2026)
The facts below come from each vendor's pricing page or project page in October 2026. Prices change, so check before you buy. Annual billing is noted where the vendor quotes it that way.
| Tool | Best for | Free option | Paid from | Worth knowing |
|---|---|---|---|---|
| UptimeRobot | Cheap, simple uptime checks | 50 monitors, 5 minute interval, 1 status page | Solo, $12 a month (annual), 60 second interval | Free plan is described as for hobby and non-profit projects |
| Better Stack | Incident handling and on-call alerts | 10 monitors and heartbeats, 1 status page | Responder license, $34 a month ($29 yearly) | SSL and domain expiry checks and 30 second intervals are on paid plans |
| Pingdom | Synthetic checks and RUM in one product | Free trial, no free plan listed | Tiered by checks or pageviews, see its pricing page | Includes synthetic monitoring and real user monitoring |
| StatusCake | Uptime plus page speed, SSL, and domain checks on every plan | 10 uptime monitors, 1 page speed, 1 SSL, 1 domain | Superior, $20.41 a month (annual) | 7 day free trial of paid plans |
| Uptime Kuma | Studios that want free software and will self-host | Free and open source (MIT license) | You pay for the server | You run, update, and secure it yourself |
| StackOS | Studios looking after many client sites | 14 day free trial | See pricing | Monitoring is one part of a studio platform, not a standalone tool |
How to Choose Between Them
- Start free if you have a handful of sites. UptimeRobot, StatusCake, or Better Stack's free plans cover basic uptime. Read the plan terms if the sites are your clients', since UptimeRobot describes its free plan as for hobby and non-profit projects.
- Pick Better Stack if on-call matters. If a person has to be paged and an incident needs a status page and a timeline, a dedicated incident tool is stronger than anything bundled into a studio platform.
- Pick Pingdom if you need RUM or scripted flows. It covers both synthetic monitoring and real user monitoring.
- Pick Uptime Kuma if you like to own your tools. It supports HTTP, TCP, keyword, DNS, ping, and Docker checks, multiple status pages, and certificate info. The cost is your time to host it, and it going down with the server it runs on, so host it somewhere separate from the sites it watches.
- Pick StackOS if the sites are your clients' and you also run the business side. More on that below.
What Studios Need From Site Monitoring
Looking after client sites adds three needs that single-site tools skip.
- One list for every site. You should see which of your 30 sites has a problem right now, not open 30 dashboards.
- Alerts that reach the right person. The designer on the project does not need to be woken for a certificate warning on a site they never touched.
- A way to show the client. Clients who never hear about a problem you fixed assume nothing happened. A monthly report turns silent work into proof.
Without that last piece, monitoring is a cost with no visible return. A report that says "99.9% uptime, certificate renewed, speed unchanged" is what keeps a care plan from looking like an expense the client can cut.
A Practical Setup, Step by Step
- List every site and who is responsible for it.
- Monitor uptime, SSL, domain expiry, and DNS for all of them, not just the important ones.
- Add speed checks monthly, and after each major update.
- Decide who gets each alert and test it by forcing a failure on a staging site.
- Send clients a short report on a fixed day each month.
- Add the monitoring steps to your handoff, using the website launch checklist, so every new site is covered from day one.
Where StackOS Fits
To be clear about the limits: StackOS monitoring is part of a studio platform. It is not a paging and on-call rotation tool, and it does not run scripted checkout flows or real user monitoring. If those matter for a client, pair it with Better Stack or Pingdom.
Frequently Asked Questions
What are the best website monitoring tools?
The best website monitoring tools depend on what you need. UptimeRobot and StatusCake suit simple uptime checks on a small budget, Better Stack suits incident handling, Pingdom covers synthetic and real user monitoring, Uptime Kuma suits people who self-host, and StackOS suits studios looking after many client sites with reports.
What is the difference between website monitoring and uptime monitoring?
Uptime monitoring checks whether a site responds. Website monitoring is wider: it also watches SSL and domain expiry, DNS changes, blocklist listings, speed, and broken pages. A site can be technically up while its certificate is about to expire or its pages take eight seconds to load.
Is there a free tool for site monitoring?
Yes. UptimeRobot, StatusCake, and Better Stack each have a free plan, and Uptime Kuma is free open source software you host yourself. Free plans limit monitors and check frequency, and some are meant for personal or non-profit use, so check the terms before using one for paying clients.
How often should uptime monitoring check my site?
Every one to five minutes is common. A five minute interval means you could learn about an outage up to five minutes late, which is fine for most brochure sites. Stores and booking sites that lose money by the minute should check more often and from more than one location.
What should I monitor besides uptime?
Monitor SSL certificate expiry, domain expiry, DNS changes, malware and blocklist listings, page speed, and any key page or form that must keep working. Expired certificates and domains are the most avoidable outages, because the dates are known weeks in advance.
What website monitoring tools work best for agencies with many client sites?
Look for one list of every site, alerts routed to the right person, and client-facing reports. Standalone tools cover uptime well but make you build the reporting. A studio platform like StackOS puts monitoring next to client records and care plan billing, while a dedicated tool like Better Stack handles on-call better.