Cron Doctor · configuration analysis
Free cron expression checker
Check five-field cron syntax, read the schedule in plain language, and preview upcoming scheduled times. Supply the timezone your scheduler actually uses; the checker cannot inspect your host.
No signup needed for analysis. Need ongoing completion monitoring? Pro covers up to 50 jobs for $9.99/month, for one owner.
Open Cron DoctorWhat you can check
- Check standard five-field Unix cron expressions and supported aliases.
- Read the schedule and upcoming times with explicit timezone context.
- See which command and runtime details an expression leaves unknown.
What remains unknown
Expression-only analysis remains partial because it has no command context. An unspecified timezone can produce an assumed UTC preview; that does not establish your scheduler’s timezone. Six-field seconds and Quartz syntax are unsupported. @reboot does not have calendar run times.
Timing example
0 2 * * * means daily at 02:00 in the scheduler’s timezone. Select UTC in Unix fallback timezone only if that is the intended zone. This expression contains no command and installs nothing.
0 2 * * *
Your configuration is sent to PingCron for analysis. It is not saved and is never executed. A static report does not establish runtime health.
Official scheduler reference · Explore ongoing monitoring
Read the five fields before checking the next run
The order is minute, hour, day of month, month, day of week. In 0 2 * * *, minute 0 and hour 2 match every date. An asterisk matches every value in its field.
| Expression | Nominal schedule |
|---|---|
*/5 * * * * | Every five minutes |
0 9 * * 1-5 | Weekdays at 09:00 |
0 2 1 * * | First day of each month at 02:00 |
Steps apply within a field: */5 is not a delay measured from the last completion. In Cronie, restricted day-of-month and day-of-week fields match either condition. Local times around daylight-saving changes need special care; a nominal preview does not prove how your deployed scheduler will execute.
Check your installed scheduler’s rules. Reference: Cronie crontab syntax. For command and heartbeat placement, use the full-job crontab validator.
Managing 21–50 jobs yourself? Pro is $9.99/month.
A free expression check answers when a job is scheduled. PingCron Pro adds ongoing monitoring for up to 50 jobs under one owner, with email, Slack, Discord, and webhook alerts when expected check-ins are missing beyond the configured grace period. Keep your scheduler; PingCron does not execute, retry, or repair jobs.
For 30 monitors and one user, monthly list prices are PingCron Pro $9.99, Healthchecks Business $20, and Cronitor Business $65. Healthchecks offers 20 free checks and 100 on Business, plus SMS/WhatsApp and phone-call credits. Cronitor Business includes 12-month retention and SMS/on-call features. Choose PingCron when its scope and channels fit; its free plan is not the largest.
USD monthly prices checked October 17, 2026; taxes, discounts, and add-ons excluded. Sources: Healthchecks pricing · Cronitor pricing.
Pro keeps 30 days of data for daily reported-outcome summaries; the individual list shows the latest 100 receipts. These are monitoring records, not application logs or proof of correct output. Shared account access starts on Team at $29/month.
Analysis needs no signup. Monitoring Free includes 5 monitors and 7-day history, with no credit card. Pro signup continues to checkout.
From a timing check to one monitored job
An expression alone cannot use the protection flow. Add the actual command from one user-crontab entry and supply the scheduler’s explicit timezone, then analyze again. In a supported report, select Protect this job and review the owning account, schedule, timezone, and grace period.
Follow the completion-reporting shell example to send a check-in after required work and output checks succeed. Confirm a real completion receipt, verify your alert destination, and test missed-run and recovery behavior on an isolated monitor. Allow for normal runtime and scheduler delay. A missing signal can also mean a reporting or network problem.