Cron Expression Builder
Build and understand cron schedule expressions visually. See the next run times instantly.
Quick Presets
0–59
0–23
1–31
1–12
0–6 (Sun=0)
Cron Syntax Reference
| Symbol | Meaning | Example |
|---|---|---|
| * | Any value | * = every minute/hour/day |
| , | List of values | 1,3,5 = at 1, 3 and 5 |
| - | Range of values | 1-5 = from 1 to 5 |
| */n | Every n units | */15 = every 15 minutes |
Frequently Asked Questions
What is a cron job?
A cron job is a scheduled task in Unix/Linux systems. The cron daemon reads a crontab file and executes commands at the specified times. Cron expressions are also used in Kubernetes CronJobs, GitHub Actions, AWS EventBridge, and many CI/CD systems.
What timezone does cron use?
By default, cron uses the system timezone. Kubernetes CronJobs and GitHub Actions use UTC. Always specify the timezone in your deployment configuration to avoid unexpected run times.
What is the difference between 5-field and 6-field cron?
Standard Unix cron uses 5 fields (minute, hour, day, month, weekday). Some systems like Spring Boot, AWS, and Quartz use a 6-field format that adds seconds as the first field. This tool uses the standard 5-field format.