Heartbeat Ping Snippet Generator
Wrap any command so it pings a heartbeat URL on success and reports failures.
Cron Heartbeat Interval & Grace Period Calculator
A heartbeat monitor alerts when a job stops checking in. Set the interval too short and you get false alarms; too long and failures go unnoticed. Enter the schedule and how long the job takes to get sensible values.
- Free
- No sign-up
- Runs in your browser
Recommended monitor settings
Upcoming runs (your time zone)
| Run starts | Ping expected around | Late if no ping by |
|---|
How to use the Cron Heartbeat Calculator
- Enter the job’s cron expression.
- Enter its typical and longest run time.
- Choose how quickly you want to hear about a missed run.
- Use the expected interval and grace period in your heartbeat monitor.
Know when a cron job doesn’t run
SensaCat gives every scheduled job a heartbeat URL and alerts your team by email, Slack or Discord when a ping is late or reports a failure.
Frequently asked questions
A monitor that expects your job to send a ping on schedule. It doesn’t watch the job directly; it alerts when an expected ping doesn’t arrive, which catches crashes, hung jobs, servers that are switched off and crontabs that were deleted.
Extra time allowed after the expected interval before a missed ping counts as a failure. It absorbs normal variation in start time and run time, so a job that runs a little long doesn’t trigger an alert.
The gap between Friday’s run and Monday’s run is much longer than the other gaps. Either set the expected interval to the longest normal gap, or use a monitor that understands cron schedules. This calculator shows both the shortest and the longest gap so you can decide.
Ping at the end, after the work succeeds; that proves the job completed. If a job can hang, also track its run time so a job that starts but never finishes is caught.
Related tools
Cron Expression Parser
Translate a cron expression into plain English and list its next runs in any time zone.
Uptime & SLA Calculator
Turn an uptime percentage into allowed downtime, or downtime into an uptime percentage.