Heartbeat monitoring
for your critical services
No credit card required

Trusted by thousands of businesses
Everything you need
Heartbeat monitoring that just works
Simple, reliable, and powerful heartbeat monitoring for modern infrastructure. No complex setup, no vendor lock-in, just reliable monitoring that scales with your business.
- Monitor anything with a heartbeat
- Servers, applications, IoT devices, backup jobs, data pipelines - if it can send an HTTP request, OnlineOrNot can monitor it. One simple curl command is all it takes.
- Zero-configuration setup
- No complex configuration files or SDKs required. Create a monitor, get a URL, send a ping. Your heartbeat monitoring is live in under 60 seconds.
- Intelligent failure detection
- Advanced scheduling with cron expressions, grace periods for late heartbeats, and smart alerting that reduces false positives while catching real issues.
- Instant multi-channel alerts
- Get notified immediately via Email, SMS, Slack, Discord, Microsoft Teams, PagerDuty, OpsGenie, Grafana OnCall, Incident.io, and more.
- Developer-friendly API
- Full REST API, webhooks, and open-source CLI tools. Integrate heartbeat monitoring into your existing workflows and infrastructure-as-code.
- Private status pages
- Share real-time status with your team and stakeholders. Perfect for internal infrastructure monitoring and service health dashboards.
- Mobile & IoT ready
- Lightweight heartbeat endpoints perfect for mobile apps, embedded devices, and IoT sensors. Monitor edge infrastructure with ease.
- Enterprise integrations
- Seamlessly integrate with your existing on-call tools like PagerDuty, Incident.io, and Opsgenie. Built for teams that take reliability seriously.
Common heartbeat monitoring use cases
See how teams use OnlineOrNot to monitor everything from servers to IoT devices
Server Health Monitoring
Send periodic heartbeats from your servers to ensure they're online and responsive.
Application Health Checks
Monitor critical application processes, background workers, and service health.
IoT Device Monitoring
Track the status of remote devices, sensors, and embedded systems.
Data Pipeline Monitoring
Ensure ETL jobs, data syncs, and batch processes complete successfully.
Software teams ❤️ OnlineOrNot
OnlineOrNot is built for scale and runs millions of uptime checks every week. Thousands of software teams, including some of the world's leading brands have already made the switch from other uptime monitors.
- Uptime Checks last week
- 11.8M
- Users
- 3,943
- Detected incidents last week
- 774
OnlineOrNot has been absolutely fantastic for my bot, Noti. It completely transformed the way I monitor online services.
The real-time notifications keep me in the loop about any downtime, allowing me to take immediate action. If you're looking for a reliable way to monitor your project's status, I highly suggest using OnlineOrNot.
Adam HMaker of NotiBet on indie hackers 🚀
I tried @RozenMD's OnlineOrNot uptime monitoring, and for a few days got notifications of 2min down time.
I thought that OnlineOrNot was wrong as Uptime Robot wasn't reporting anything.
Turns out it was the other way around.
Khaled BentoumiFounder of Data to Page
We've been using OnlineOrNot and it has been a life saver.
It, by far, has been one of the most responsive uptime services we've tried and it only gets better and better as time goes on.
Alex BowlesFounder of CasterlabsI just set up some site aliveness checks for @Archium_io with @RozenMD's OnlineOrNot.
Took me less than five minutes and it was completely self-explanatory, not to mention gorgeous. Seriously good experience.
Great job, Max! 👏👏
Graham LeaFounder of Archium.ioOnlineOrNot by @RozenMD is all one needs
It is easy to set up and very reliable. I have been using it for almost an year now.
Rajat SaxenaFounder of CourseLit
I'm using OnlineOrNot to monitor my @cloakist customers' sites, so I can respond quickly if they stop working
Love it. Super clean interface, very intuitive. Particularly impressed at how it can wait for full page load
Thanks @RozenMD for making this awesome tool!
Louis BarclayFounder of CloakistOnlineOrNot does the job for me.
Charles MillerSoftware Architect at Atlassian
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