Your site went down at 3 a.m., and you found out from a client at 9 a.m. Sound familiar? Every minute of downtime means lost revenue, search rankings, and audience trust. At the same time, no one's going to sit and manually refresh the page every five minutes, that's what monitoring services exist for.

The problem is that the market is flooded with tools: from tiny utilities to enterprise platforms with six-figure price tags. How do you choose one that will actually warn you about downtime rather than just eat your budget?

Below are 16 online services for website uptime monitoring that we've selected and tested. Free, paid, for personal projects and for enterprise, each with its own specialization.

💡 Quick overview:

• Choose a free service to start: UptimeRobot (50 sites) or Freshping (50 URLs with per-minute checks) will cover the needs of a small project without a budget.
• If you need more speed and features, take a look at Better Uptime (30-second checks and phone calls) or Cronitor (browser-based JS testing).
• For self-hosting and full control over your data, deploy Uptime Kuma in Docker in 5 minutes, open-source and with no monitor limits.

Comparison table

1. Uptrends

Uptrends is a market veteran with more than 30 monitoring points around the world. The service checks site availability from different geographic locations and sends an email notification as soon as it detects a problem.

The main feature is a customizable dashboard with availability graphs and error breakdown by type. Data can be exported to PDF or Excel to show clients or management a monthly report. On the downside, the free version has a fixed check interval (10 minutes), and proper alerts like SMS are only available on paid plans.

Pros: powerful dashboard analytics, report export, 30+ check points.

Cons: weak free plan, no push notifications.

🔗 Uptrends on official site

2. Dotcom-Monitor

Dotcom-Monitor is an enterprise platform that covers not only uptime but also performance, web application functionality, APIs, and servers. With 25+ global monitoring points and a minimum check interval of 1 minute, this is a tool for those who need instant response.

Alerts come via SMS, email, and phone calls, the latter is critically important when an incident happens at night. The service offers a 30-day free trial with no restrictions, but after that, only paid plans.

Pros: phone calls, 1-minute interval, all types of monitoring in one window.

Cons: no permanent free plan, overkill for a personal blog.

🔗 Dotcom-Monitor on official site

3. StatusCake

StatusCake has been operating since 2012 and has accumulated an impressive set of features since then. On one free plan you get monitoring for HTTP, TCP, SSH, DNS, SMTP, PING, and PUSH, plus alerts via email, Slack, Telegram, and Discord.

Beyond pure uptime, the platform tracks page load speed, SSL certificates, domains, and even scans the site for viruses. This makes StatusCake a hybrid between monitoring and security auditing. Paid plans remove branding and add SMS notifications.

Pros: very generous free plan, virus scanning, SSL and domain monitoring.

Cons: SMS only on paid plans, interface slightly overloaded.

🔗 StatusCake on official site

4. Sematext Synthetics

Sematext Synthetics is part of the Sematext ecosystem, tailored for synthetic monitoring: HTTP requests, browser scenarios, API checks. The service tracks Core Web Vitals, network time, third-party API performance, and SSL certificates from specified locations.

Check intervals range from 1 minute to once an hour. Alerts go to email, Slack, VictorOps, Twilio, PagerDuty, and custom webhooks. The free period is 14 days, then plans start from $29/month (40 HTTP monitors + 5 browser) with a pay-as-you-go option from $2 per monitor.

Pros: deep synthetic monitoring, pay-as-you-go, Core Web Vitals.

Cons: short trial, entry barrier for beginners.

🔗 Sematext Synthetics

5. HetrixTools

HetrixTools is one of the few services offering per-minute monitoring on a free plan. In addition to standard HTTP(S) checks, the platform performs PING/MTR samples on every outage, monitors SSL and domain expiration, detects nameserver changes, and monitors server resources.

There are more than a dozen notification channels: email, SMS, Telegram, Slack, Discord, Microsoft Teams, PagerDuty, OpsGenie, and even Twitter. A built-in status page allows you to show clients the current state of services without third-party integrations.

Pros: per-minute monitoring for free, server monitoring, status page.

Cons: interface not the most modern, no mobile app.

🔗 HetrixTools on official site

6. AlertBot

AlertBot is a tool for the mid-market and enterprise segment. Instead of simple HTTP requests, it uses real web browsers to test performance, which allows catching bottlenecks at the rendering and user experience level.

The company provides personalized assistance with setting up web transaction monitoring and generates detailed reports with clear indications of the source of the problem. There's no free plan, but there's demo access to evaluate capabilities.

Pros: browser-based testing, personalized support, detailed reports.

Cons: no free plan, overkill for small sites.

🔗 AlertBot on official site

7. Cronitor

Cronitor stands out for its speed: check interval every 30 seconds from 12 global locations. This is one of the fastest downtime detectors on the market. The service is tailored for developers: custom request headers, cookies, page content asserts, and real browser testing of JavaScript applications.

There's a free plan, it includes basic monitoring and email alerts. Paid plans add SMS, Slack, PagerDuty, OpsGenie, and remove the limit on the number of checks.

Pros: 30-second interval, browser-based JS testing, excellent UI.

Cons: free plan is limited on alerts, somewhat complex for non-developers.

🔗 Cronitor on official site

8. Checkly

Checkly is an active monitoring platform for teams using a modern stack. Monitoring is configured via JavaScript: you write browser check scenarios with open source code, and for APIs, full HTTP requests with asserts and Node.js scripts.

The service integrates with GitHub and Terraform, allowing you to manage checks as code. There's a free plan for developers, scaling on a usage basis. Checkly clients include Vercel, 1Password, Humio, and other technology companies.

Pros: monitoring as code, CI/CD integration, programmable checks.

Cons: requires technical skills, overkill for a static site.

🔗 Checkly on official site

9. Uptime Robot

Uptime Robot is probably the most popular free monitoring on the market. The free plan includes 50 URLs with a 5-minute check interval and email alerts. For a personal blog, portfolio, or small business, this is more than enough.

The service can also monitor ports (FTP, SMTP, POP3, IMAP, custom) and track keywords on a page, a simple way to protect against defacement. Paid plans add SMS, voice calls, and per-minute intervals.

Pros: 50 URLs for free, port monitoring, easy setup.

Cons: 5-minute interval on free plan, no server monitoring.

🔗 Uptime Robot on official site

10. Uptime.com

Uptime.com is an enterprise platform with monitoring from 30+ points worldwide and detailed response time reports. In addition to HTTP(S), the service checks SSH, DNS, PING, POP, IMAP, and other protocols.

Alerts come via email, SMS, push notifications, webhooks, and Twitter. Separately worth noting are the built-in security checks that go beyond typical uptime monitoring. There's no free plan, the product is oriented toward businesses with an appropriate budget.

Pros: 30+ locations, security checks, all protocols.

Cons: no free plan, price above average.

🔗 Uptime.com on official site

11. Uptimia

Uptimia is a simple and visual service for basic monitoring. The free plan includes checks with a 5-minute interval from 5 data centers and email notifications. On paid plans, the interval is reduced to 30 seconds.

Reporting is Uptimia's strong suit: beautiful response time graphs broken down by DNS, Connects, Send, Wait, and Receive help quickly diagnose at which stage performance is dropping.

Pros: clear response time analytics, simple start.

Cons: only 5 locations on free plan, only email alerts for free.

🔗 Uptimia on official site

12. Uptime Kuma

Uptime Kuma is an open-source alternative to commercial services. Deploys in Docker in 5 minutes: one docker-compose up, and you have your own uptime monitor with a web interface. Supports HTTP/HTTPS, TCP ports, DNS, Docker containers, push monitoring, and dozens of alert channels: email, Telegram, Slack, Discord, webhooks, and others.

Data is stored on your server, there are no limits on the number of monitors, status pages are customizable to your brand. The project has 60,000+ stars on GitHub, an active community, and regular updates. Perfect choice for those who want full control over their data and don't want to pay for a subscription.

Pros: completely free, self-hosted, 5-minute Docker installation, no monitor limits.

Cons: requires your own server (from a few dollars per month for VPS), no global check points, no real-browser monitoring.

🔗 Uptime Kuma on GitHub

13. Freshping

Freshping is a product of the Freshworks ecosystem (formerly known as Insping). The free plan is one of the best on the market: 50 URLs, 10 global locations, per-minute interval, and 6 months of data retention.

A built-in status page allows you to inform users about incidents in real time. Integrations with Slack, Twilio, Freshdesk, Zapier, and other Freshworks products make it a natural choice for those already in this ecosystem.

Pros: 50 URLs for free with per-minute interval, status page, Freshworks ecosystem.

Cons: tied to Freshworks ecosystem, SMS notifications are paid.

🔗 Freshping on official site

14. WebGazer

WebGazer combines monitoring of websites, cron jobs, and IoT devices in one window. In addition to standard HTTP checks, the service tracks scheduled tasks and sends instant downtime notifications.

A beautiful status page comes out of the box. There's a free plan that covers basic needs, paid plans add SMS alerts, reduce check intervals, and increase the number of monitors.

Pros: cron and IoT monitoring, stylish status page.

Cons: fewer monitoring points than giants, SMS only paid.

🔗 WebGazer on official site

15. Pingdom

Pingdom is one of the oldest and most authoritative tools in the niche. More than 100 monitoring points worldwide and per-minute checks make it a standard for large projects. The service tracks availability, load speed, and transactions.

Unfortunately, the free plan is closed, after the SolarWinds acquisition the product moved to a fully paid model. However, in terms of functionality and geographic coverage, Pingdom remains one of the leaders.

Pros: 100+ points, transaction monitoring, brand with history.

Cons: no free plan, price is high for small projects.

🔗 Pingdom on official site

16. Better Uptime

Better Uptime (part of the Better Stack platform) is one of the most modern tools in this selection. Setup takes 3 minutes, after which the service calls you on the phone with every site outage. The free plan includes basic monitoring, paid plans offer unlimited phone calls.

Out of the box: HTTP(S), PING, SSL, TLD, and cron monitoring, screenshots and error logs of incidents, 100+ integrations (Slack, Teams, Heroku, AWS, and others). Beautiful interface and thoughtful incident management make it the best choice for teams that need speed of response.

Pros: phone calls on outage, 30-second interval, 100+ integrations.

Cons: free plan is limited on calls, relatively young product.

🔗 Better Uptime on official site

⁉️🤔 Frequently asked questions

What is website uptime monitoring?

Uptime monitoring is automatic checking of site availability at specified intervals from different points around the world. The service sends an HTTP(S) request to your URL and waits for a response with code 200. If there's no response or there's an error code, an incident is recorded and a notification is triggered. Good monitoring also tracks response time, SSL certificates, and port availability.

What's the difference between synthetic monitoring and real user monitoring?

Synthetic monitoring runs artificial checks from specified locations on a schedule. It's predictable and reproducible, but doesn't see real user problems. Real User Monitoring (RUM) collects data from the browsers of live visitors, it shows how the site actually works, but won't warn you about downtime at night when there's no traffic. For the full picture, both approaches are used.

What check interval is sufficient for an online store?

For a store with turnover, 1 minute. A five-minute interval means you could find out about downtime 4 minutes 59 seconds after the fact: in that time you can lose dozens of orders. Large retailers use 30-second intervals and redundant monitors from different locations. For a blog or landing page, 5 minutes is fine.

Is it necessary to pay for monitoring?

No. Uptime Robot and Freshping give 50 URLs for free with a decent interval. This is enough for most small projects. Paid plans are needed when SMS or voice notifications are critical, per-minute (or 30-second) intervals, and monitoring from dozens of locations.

What if the monitoring service itself goes down?

Rare but real scenario. Solution: two independent monitors, for example, main on Uptime Robot and backup on Freshping (both free). If one service doesn't respond, the second will send an alert. For critical infrastructure, they also set up a self-hosted solution like Uptime Kuma on a separate VPS.

Is it worth overpaying for enterprise?

If you have one WordPress site, Uptime Robot or Freshping is enough. Both are free, set up in two minutes, and reliably send emails on downtime. For an agency with dozens of client projects, StatusCake or HetrixTools: more features on the free start, plus status pages for clients. For an online store with serious turnover, Better Uptime or Cronitor with a 30-second interval and phone calls. And for enterprise infrastructure, Pingdom or Dotcom-Monitor with global coverage and transaction monitoring.

The main rule: monitoring without an alert that you actually see is useless. Set up at least two channels (email + messenger or SMS) and verify that notifications are getting through before the site really goes down.