Cron Expression Builder & Explainer
Build a standard 5-field cron schedule visually or type one directly. Get a plain-English description and a live preview of the next five run times — all calculated in your browser.
Quick presets
Cron expression
Meaning—
Visual builder
Next 5 runtimes
Frequently asked questions
What do the five fields mean?
A standard cron expression has five space-separated fields, in order: minute (0–59), hour (0–23), day of month (1–31), month (1–12), and day of week (0–6, where both 0 and 7 mean Sunday). An asterisk (*) means every value.
How are the next run times calculated?
Entirely in your browser. The expression is evaluated minute-by-minute from the current time, up to one year ahead, and the first five matches are shown in your local timezone. Nothing is uploaded.
What if both day-of-month and day-of-week are set?
Following standard Vixie cron behaviour, when both are restricted (neither is *) a run fires when either matches. If one is *, both must match (logical AND).
About cron
Cron is a time-based job scheduler used by Unix-like operating systems and countless cloud platforms. A schedule is written as a compact crontab expression of five fields: minute hour day-of-month month day-of-week. Each field accepts a wildcard (*), a single value, a comma-separated list (1,15), a range (9-17), or a step value (*/15 or 0-30/10). This tool helps you compose valid expressions, understand them in plain English, and verify exactly when they will fire next — useful for scheduling backups, batch jobs, newsletters, reports, and CI pipelines.
0–59
0–23
1–31
1–12
0–6 (0/7 = Sun)