Cron Expression Basics: Read a Schedule Before You Use It
Understand the five common cron fields and avoid scheduling mistakes in jobs and automations.
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The five common fields
A common cron expression has five fields: minute, hour, day of month, month and day of week.
The compact format is powerful, but that compactness is exactly why mistakes happen. A small change can turn a weekly job into a job that runs many times per day.
Ranges, lists and steps
A range such as 9-17 means values from 9 through 17. A list such as 1,3,5 means only those values. A step such as */15 means every 15 values.
Before saving a scheduled task, explain the expression in plain English and check whether it matches the real business requirement.