Cron Expression Generator
Compose a standard 5-field cron expression (minute, hour, day of month, month, day of week) with dropdowns, and read back what it means in plain English.
How to use this tool
- Start from a preset, or fill the five fields: minute, hour, day of month, month, day of week.
- Use * for any value, commas for lists (1,15), hyphens for ranges (1-5), and slashes for steps (*/15).
- Read the plain-English description to confirm the schedule, then copy the expression.
How it works
Standard cron uses five space-separated fields: minute (0–59), hour (0–23), day of month (1–31), month (1–12), and day of week (0–6, Sunday = 0). A job runs when the current time matches all applicable fields.
Watch for dialect differences: some systems add a seconds field (Quartz uses six or seven fields), some accept @daily shortcuts, and non-standard implementations disagree about what happens when both day-of-month and day-of-week are set. Always check your scheduler's documentation.
Frequently asked questions
What does */15 mean in cron?
Every 15 units of that field. In the minute field, */15 runs at :00, :15, :30, and :45 of every hour.
How do I run a job every weekday at 9am?
0 9 * * 1-5 — minute 0, hour 9, any day of month, any month, Monday through Friday.
Why doesn't my cron expression work in my scheduler?
Cron formats vary. Quartz expects a seconds field first, some systems use 7 for Sunday, and cloud schedulers each have quirks. This tool builds standard 5-field POSIX-style expressions.