Cron Expression Builder

What the cron expression builder does

Cron schedules jobs with a terse five-field expression — minute, hour, day of month, month, day of week. This builder lets you set each field with dropdowns and presets ("every 15 minutes", "every day at 9am", "every Monday"), writes the expression for you, translates it back into plain English, and previews the next five run times so you can confirm it does what you meant.

How to build a cron expression

1. Pick a preset, or set each field (minute / hour / day / month / weekday).
2. Read the human-readable description to confirm the schedule.
3. Check the next 5 execution times, then copy the expression.

Why cron is easy to get wrong

The syntax is compact and unforgiving: * means "every", */5 means "every 5", ranges use 1-5, and lists use 1,15. Mixing up day-of-month and day-of-week, or forgetting that both being set is an OR (not AND), silently ships a job that runs at the wrong time. Seeing the plain-English readout and the next run times catches the mistake before it hits production.

Cron schedules are relative; to see where an absolute time or Unix timestamp falls, use the timestamp converter. Scheduling containers? Wire the job into a Docker Compose stack.