Crontab Guru

A cron expression is a string of five fields separated by spaces that defines a schedule for automated tasks. It is used by Unix‑based systems and many job schedulers. The five fields represent: minute (0‑59), hour (0‑23), day of month (1‑31), month (1‑12), and day of week (0‑7, where both 0 and 7 mean Sunday). Special characters like * (any), , (list), - (range), and / (step) allow flexible schedules.

• Minute: 0–59
• Hour: 0–23
• Day of Month: 1–31
• Month: 1–12 (or names like JAN, FEB)
• Day of Week: 0–7 (0 and 7 = Sunday, 1 = Monday … 6 = Saturday)

Special characters: * matches all values; , separates items; - denotes a range; / defines a step (e.g., */15 means every 15 units).

Many systems accept convenient aliases that replace the full five‑field expression:

• @yearly / @annually — midnight on January 1st (0 0 1 1 *)
• @monthly — midnight on the 1st of every month (0 0 1 * *)
• @weekly — midnight every Sunday (0 0 * * 0)
• @daily / @midnight — midnight every day (0 0 * * *)
• @hourly — at the start of every hour (0 * * * *)

This tool recognizes all these shorthands automatically.

Common mistakes include:

• Using both day‑of‑month and day‑of‑week fields together – standard cron requires both conditions to be true (AND logic), which often leads to surprise.
• Forgetting that week starts with Sunday (0) and that 7 is also Sunday.
• Month and day numbering starting from 1, not 0.
• Step values (/) that don’t align with the allowed range.

Preview the calculated execution times with this tool to verify your schedule before deploying.

The tool starts from the current minute and iterates forward, checking each minute against your cron expression. It respects all special characters, ranges, lists, and the AND rule for day‑of‑month and day‑of‑week. The results are displayed in your local time zone and in UTC, making it easy to coordinate across time zones. No data leaves your browser.