Cron Next Run Calculator
See exactly when a cron expression will fire next — the next 5, 10 or 20 runs in your local time.
This tool runs 100% in your browser. Your data is never uploaded, stored, or logged.
Upcoming runs (your local time)
Type a cron expression to see exactly when it will fire next.
About this tool
Knowing what a cron expression means is half the story; knowing when it will actually fire is the other half. This calculator computes the next runs of any standard 5-field expression — including tricky month-boundary and DOM/DOW combinations — from now or from any date you choose.
Each run shows the weekday, exact timestamp and relative time ("in 3 hours").
How to use it
- Enter a cron expression, e.g.
30 3 * * MON-FRI. - Pick how many upcoming runs to list.
- Optionally set a custom start date (YYYY-MM-DD HH:MM).
- Times display in your browser's timezone — servers often use UTC, so compare carefully.
Useful ways to apply it
- Verifying a backup job really runs at 3:30 AM on weekdays.
- Planning maintenance windows around scheduled tasks.
- Debugging "why didn't my cron run?" by checking the real schedule.
- Testing edge cases like
0 0 31 * *(skips 30-day months).
Frequently asked questions
What timezone are results in?
Your browser's local timezone (shown under the results). Server crontabs usually run in the server's timezone — often UTC — so translate accordingly.
How are impossible dates handled?
Expressions that can never match (like Feb 30) are detected after scanning ~5 years of minutes, and you get a clear error instead of an infinite spinner.
Does it use OR logic for day fields?
Yes — when both day-of-month and day-of-week are restricted, a run happens when either matches, exactly like real cron.
Privacy
This tool runs 100% in your browser. Your data is never uploaded, stored, or logged.