Cron Expression Generator & Explainer
Build a schedule with dropdowns, or paste an expression and read it back in plain English — field by field, with the next 10 runs in the timezone of your choice.
Human-readable schedule:
Every day at 9:00 AM
Field by field
| Field | Value | Allowed | Means |
|---|
Next 10 Run Times
A cron expression carries no timezone of its own — it means whatever the scheduler running it says it means.
Ready to automate?
Simple Data Foundry supports cron-based scheduling — automate your data syncs on any schedule.
Frequently Asked Questions
What is a cron expression?
A cron expression is a string of five fields (minute, hour, day of month, month, day of week) that defines a schedule for recurring tasks. For example, "0 9 * * 1" means every Monday at 9:00 AM.
What does * mean in cron?
The asterisk (*) is a wildcard that means "every" value for that field. For example, * in the hour field means "every hour".
What does */15 mean?
A slash defines a step. */15 in the minute field means every 15th minute starting from 0 — so :00, :15, :30 and :45. You can combine it with a range: 9-17/2 means every second hour between 9 and 17.
How do day-of-month and day-of-week interact?
When both are restricted, standard cron treats them as OR, not AND — "0 0 1 * 1" fires on the 1st of the month AND on every Monday. If you want a single weekday, leave day-of-month as *. This tool follows the same OR behaviour so the preview matches what a real scheduler does.
What timezone does a cron expression run in?
Cron itself has no timezone — the schedule is interpreted in whatever zone the scheduler runs in. Use the timezone selector here to preview the run times in the zone you actually care about, and check which zone your scheduler uses before relying on an hour-specific schedule.
What happens during daylight saving changes?
A wall-clock time that does not exist on the day the clocks go forward is skipped, and the preview skips it too. Times in the repeated hour when clocks go back run on the first pass. Schedules on */15 or hourly steps are unaffected in practice — hour-specific daily jobs are the ones to watch.
Can I use this for AWS, GCP, or Azure schedules?
Yes. Standard 5-field cron expressions work with most cloud schedulers including AWS CloudWatch, GCP Cloud Scheduler, and Azure Logic Apps (some may need a 6th field for seconds).