Cron Expression Anatomy
*Minute (0–59)
*Hour (0–23)
*Day of month (1–31)
*Month (1–12)
*Day of week (0–7)
Common Cron Examples
* * * * *Every minute
0 * * * *At minute 0 of every hour (every hour on the hour)
0 9 * * *Every day at 9:00 AM
0 9 * * 1-5Every weekday (Mon–Fri) at 9:00 AM
*/15 * * * *Every 15 minutes (:00, :15, :30, :45)
0 0 1 * *First day of every month at midnight
0 0 * * 0Every Sunday at midnight
30 23 * * 5Every Friday at 11:30 PM
How to Use It
1
Open the tool
Go to Database & Code and scroll to the Cron Expression Builder.
2
Set your schedule
Select minute, hour, day of month, month and day of week using the controls. Use * for "every".
3
Check the description
The human-readable description confirms when the job will run — e.g. "Every weekday at 9:00 AM".
4
Copy the expression
Copy the 5-field cron string and paste it into your crontab, GitHub Actions, AWS EventBridge or CI config.
Pro Tips
💡Cron runs in the server's local timezone. If you need UTC scheduling, set the server timezone to UTC or use a cloud scheduler that lets you specify the timezone explicitly.
💡Use
*/n for "every n units" — */5 * * * * = every 5 minutes. Use a-b for ranges — 0 9-17 * * 1-5 = every hour from 9am to 5pm on weekdays.💡In GitHub Actions, cron schedules use UTC. Add 5 minutes of buffer before an expected run time — GitHub Actions does not guarantee exact-second execution.
Frequently Asked Questions
What is a cron expression?
Five space-separated fields defining a recurring schedule:
minute hour day-of-month month day-of-week. Example: 0 9 * * 1-5 = 9am every weekday.What does * mean?
"Every" for that field.
* * * * * = every minute. 0 * * * * = minute 0 of every hour.How do I run every 15 minutes?
*/15 * * * * — the */n step notation runs at :00, :15, :30 and :45 of every hour.5-field vs 6-field cron?
Standard cron has 5 fields. Some systems (AWS EventBridge, Spring) add a 6th field for seconds at the beginning. Check your scheduler's documentation.
Build your cron expression now
Open the Cron Expression Builder and generate any recurring schedule visually — free, no login required.
Open Cron Builder →