Free monitoring tool
Cron Expression Checker
Validate a five-field cron expression and preview its next five run times in UTC without contacting a server.
Read the five fields
The fields are minute, hour, day of month, month and day of week. For example, */5 * * * * runs every five minutes; 0 2 * * * runs daily at 02:00 in the scheduler’s configured timezone. This preview uses UTC.
Match your actual scheduler
Cron implementations differ in special syntax and in how day-of-month and day-of-week interact. Compare the preview with the scheduler you deploy, and account for its timezone and daylight-saving behavior. An expression can be valid while the command itself fails.
Monitor completion, not just scheduling
Add a heartbeat after a successful job and choose an expected interval and grace period appropriate to its runtime. A missing heartbeat can then identify silent backup, ETL or billing-job failures. This tool only calculates dates; it never executes a command.
Common questions
Does this support seconds as a sixth field?
No. Use five fields. Seconds-based schedulers use a different expression format.
Does a valid expression mean my job ran?
No. Check scheduler logs and add a success heartbeat to verify completion.