Cron Expression Builder & Explainer
Understand any cron expression in plain English and preview its next run times — 100% in your browser.
minute · hour · day-of-month · month · day-of-week
About Cron Expression Builder & Explainer
Paste a standard 5-field cron expression (minute, hour, day-of-month, month, day-of-week) and get a readable explanation of when it runs, plus a preview of the next five run times in your local time zone. Ranges (1-5), lists (1,15,30), steps (*/15) and month/weekday names (JAN, MON) are all supported.
Use the presets to start from a common schedule. Everything is computed locally in your browser; nothing is uploaded.
Weekday mornings
0 9 * * 1-5
At minute 0 past hour 9, on Monday, Tuesday, Wednesday, Thursday, Friday.
The tool also lists the next five run times for the expression.
Frequently asked questions
What do the five fields mean?
In order: minute (0–59), hour (0–23), day-of-month (1–31), month (1–12) and day-of-week (0–7, where 0 and 7 are Sunday).
Does it support steps, ranges and lists?
Yes — */15 (every 15), 1-5 (a range), 1,15,30 (a list) and combinations, plus month and weekday names like JAN and MON.
How are day-of-month and day-of-week combined?
Following cron convention, when both are restricted the schedule runs when either matches; if only one is set, just that one applies.
Which time zone are the next runs in?
Your browser's local time zone. The calculation runs entirely on your device.