What a cron expression is
It's the standard Unix/Linux notation for scheduling recurring tasks, with 5 space-separated fields: minute, hour, day of month, month, and day of week. For example, 0 3 * * 1 means "every Monday at 3 AM".
When to use it
Useful for double-checking that a cron expression you wrote (for a crontab, a GitHub Actions workflow, a scheduled job) really represents the schedule you intended, without needing to memorize the syntax.
Frequently asked questions
Does this tool support 6-field expressions (with seconds)?
The focus is the standard 5-field Unix/Linux cron format; some systems use a 6-field variant with seconds, which may not be parsed correctly here.
What does the asterisk (*) mean?
It means "any value" in that field — for example, an asterisk in the month field means "every month".