25 Monitor Types Compared: What Every Monitoring Tool Actually Checks (2026)

Most uptime monitoring tools check one thing: is your URL returning a 200 status code? That was enough in 2015. In 2026, production infrastructure spans HTTP endpoints, SSL certificates, DNS records, mail servers, WebSocket connections, APIs with complex JSON responses, scheduled cron jobs, and private services behind firewalls. A single HTTP ping cannot tell you that your SSL certificate expires tomorrow, that your DNS records were hijacked, or that your SMTP server stopped accepting mail.

We compared the monitor types offered by six popular monitoring platforms — Monitorion, UptimeRobot, Better Stack, StatusCake, Pingdom, and HetrixTools — to show exactly what each tool can and cannot check. The differences are significant and often surprising.

The Complete Monitor Type Comparison

Monitor Type	Monitorion	UptimeRobot	Better Stack	StatusCake	Pingdom	HetrixTools
HTTP/HTTPS	Yes	Yes	Yes	Yes	Yes	Yes
Keyword Check	Yes	Yes	Yes	Yes	Yes	No
Ping (ICMP)	Yes	Yes	No	Yes	No	Yes
Port (TCP/UDP)	Yes	Yes	No	Yes	No	Yes
SSL Certificate	Yes	Yes	Yes	Yes	Yes	Yes
Domain Expiry	Yes	Yes	No	Yes	No	No
DNS Records	Yes	Yes	No	Yes	No	No
Heartbeat / Cron	Yes	Yes	Yes	No	No	No
SMTP	Yes	No	No	Yes	No	No
IMAP	Yes	No	No	No	No	No
POP3	Yes	No	No	No	No	No
FTP	Yes	No	No	No	No	No
WebSocket	Yes	No	No	No	No	No
GraphQL	Yes	No	No	No	No	No
JSON API Assertions	Yes	No	No	No	No	No
Content Change	Yes	No	No	No	No	No
Broken Links	Yes	No	No	No	No	No
Mixed Content	Yes	No	No	No	No	No
Security Headers	Yes	No	No	No	No	No
Lighthouse	Yes	No	No	Yes	Yes	No
Screenshot	Yes	No	Yes	No	No	No
Multi-Step	Yes	No	Yes	No	Yes	No
Redirect Chain	Yes	No	No	No	No	No
WHOIS Change	Yes	No	No	No	No	No
Blacklist / DNSBL	Yes	No	No	No	No	Yes
Sitemap Validation	Yes	No	No	No	No	No

Total monitor types: Monitorion 25, UptimeRobot 8, Better Stack 5, StatusCake 8, Pingdom 5, HetrixTools 5.

Why Monitor Types Matter More Than Monitor Count

Many tools compete on how many monitors you get in their free tier. UptimeRobot gives you 50 free monitors. HetrixTools gives you 15. Monitorion gives you 10. But a monitor that only checks HTTP status codes is fundamentally limited — you need five separate services to do what one comprehensive monitoring setup can do with different check types.

Consider a typical SaaS application. You need to monitor the website (HTTP), the SSL certificate (SSL), the DNS records (DNS), the API health endpoint (JSON API), the mail server (SMTP), the WebSocket server (WebSocket), background jobs (Heartbeat), and the domain registration (Domain Expiry). With a tool that only offers HTTP monitoring, you need 8 separate monitors and still cannot check half of those. With Monitorion, you set up 8 monitors of different types and cover every layer of your stack from a single dashboard.

The Monitor Types No One Else Offers

WebSocket Monitoring

Real-time applications — chat, live dashboards, collaborative editors, trading platforms — depend on WebSocket connections. An HTTP ping to your server tells you nothing about whether WebSocket connections can be established and messages can flow. Monitorion connects to your WebSocket endpoint, performs the upgrade handshake, optionally sends a test message, and verifies the response. No other general-purpose monitoring tool offers this.

GraphQL Monitoring

GraphQL APIs do not follow REST conventions. A GraphQL endpoint always returns 200, even when the query fails — errors are in the response body, not the status code. Monitorion sends your actual GraphQL query, checks for the errors field in the response, and verifies that the expected data structure is returned. HTTP monitoring would report your broken GraphQL API as "up."

JSON API Assertions

Your API returns 200, but is the data correct? JSON API monitoring lets you define assertions on the response body using JSONPath expressions. Check that $.status equals "healthy", that $.data.length is greater than zero, or that $.version matches your expected release. This catches the insidious failures where the endpoint is technically reachable but returning stale, empty, or incorrect data.

Content Change Detection

Monitor any web page for unauthorized changes. Monitorion hashes the page content and alerts you when it changes. This catches defacements, accidental deployments, CDN cache poisoning, and third-party script modifications. Especially valuable for compliance-regulated industries where you need to know immediately if page content was altered.

Security Headers Validation

Your site might be returning 200, but is it sending the right security headers? Monitorion checks for Content-Security-Policy, Strict-Transport-Security, X-Frame-Options, X-Content-Type-Options, and Referrer-Policy. A missing CSP header is an open invitation for XSS attacks. Get a security grade (A through F) and know immediately when a deployment accidentally removes a critical header.

Redirect Chain Monitoring

When you change hosting providers, set up URL redirects, or migrate to a new domain, redirect chains can break silently. Monitorion follows each hop, records the full chain, and alerts you when the final destination changes or a redirect loop is detected.

WHOIS Change Detection

Domain hijacking is a real threat. Monitorion monitors your domain's WHOIS records — registrar, nameservers, status flags, and update dates — and alerts you when anything changes. If someone transfers your domain or changes your nameservers, you will know within minutes.

Alert Channel Comparison

Channel	Monitorion	UptimeRobot	Better Stack	StatusCake	Pingdom	HetrixTools
Email	Yes	Yes	Yes	Yes	Yes	Yes
SMS	Included	Credits	Included	Yes	Credits	Yes
Slack	Yes	Yes	Yes	Yes	Yes	Yes
Discord	Yes	Yes	No	Yes	No	Yes
Telegram	Yes	Yes	No	No	No	Yes
Microsoft Teams	Yes	Yes	Yes	Yes	No	Yes
Google Chat	Yes	No	No	No	No	No
PagerDuty	Yes	Yes	Yes	Yes	Yes	Yes
Webhook	Yes	Yes	Yes	Yes	Yes	Yes

Monitorion is the only platform that includes Google Chat as a native alert channel. Monitorion also includes SMS credits in every paid plan (50 to 500 per month depending on tier) rather than charging per message.

Multi-Region Monitoring and Private Workers

False alarms are the fastest way to make your team ignore real alerts. Monitorion checks from 5 regions (Frankfurt, London, Virginia, Los Angeles, Singapore) and uses majority-vote consensus — at least 3 of 5 regions must confirm a failure before alerting. UptimeRobot retries from a different location. Better Stack uses 3+ location confirmation. Pingdom has 100+ locations but simpler retry logic.

For services behind firewalls, Monitorion offers an open-source private worker (github.com/monitorion/monitorion-worker) that runs inside your network. No inbound ports required. None of the other five tools offer an open-source, self-hosted worker agent.

The Bottom Line

If you only need to check whether a URL returns 200, most tools will work. But modern infrastructure requires monitoring SSL certificates, DNS records, API responses, mail servers, WebSocket connections, and scheduled jobs — all from one dashboard.

• Choose UptimeRobot if you need many HTTP monitors on a budget.
• Choose Better Stack if you need integrated log management alongside basic uptime checks.
• Choose Monitorion if you need comprehensive monitoring across your entire stack — without paying for multiple tools or per-responder fees.

Try Monitorion free — 10 monitors, 6 check types, no credit card required.