How It Works
A cron expression is a string of five fields separated by spaces. Each field controls when a scheduled task runs. The fields are evaluated left to right:
┌──────────── minute (0–59)
│ ┌────────── hour (0–23)
│ │ ┌──────── day of month (1–31)
│ │ │ ┌────── month (1–12)
│ │ │ │ ┌──── day of week (0–6, 0 = Sunday)
│ │ │ │ │
* * * * *Use the visual builder above to select values for each field, or pick a quick preset. The tool generates the expression in real time and calculates the next 5 execution times based on your current system clock. Everything runs in your browser — no data is sent to any server.
Cron Expression Syntax
| Field | Allowed Values | Special Characters |
|---|---|---|
| Minute | 0–59 | * , - / |
| Hour | 0–23 | * , - / |
| Day of Month | 1–31 | * , - / |
| Month | 1–12 | * , - / |
| Day of Week | 0–6 (0 = Sunday) | * , - / |
*— matches every possible value for that field.,— separates a list of specific values (e.g.1,15means the 1st and 15th).-— defines an inclusive range (e.g.1-5means Monday through Friday)./— defines a step interval (e.g.*/10means every 10 units).
Common Cron Expressions
| Expression | Description |
|---|---|
* * * * * | Every minute |
*/5 * * * * | Every 5 minutes |
0 * * * * | Every hour (at minute 0) |
0 0 * * * | Every day at midnight |
0 9 * * 1 | Every Monday at 9:00 AM |
0 8 * * 1-5 | Every weekday at 8:00 AM |
0 0 1 * * | First day of every month at midnight |
0 0 * * 0 | Every Sunday at midnight |
0 */6 * * * | Every 6 hours (at minute 0) |
30 2 * * * | Every day at 2:30 AM |
FAQ
What is a cron expression?
A cron expression is a string of five space-separated fields that define a schedule for recurring tasks. It was originally created for the Unix cron daemon but is now used in CI/CD pipelines, cloud schedulers (AWS EventBridge, Google Cloud Scheduler), task queues, Kubernetes CronJobs, and countless other systems. Each field specifies allowed values for minute, hour, day of month, month, and day of week.
How many fields does a cron expression have?
The standard cron expression has 5 fields: minute, hour, day of month, month, and day of week. Some systems (like Quartz Scheduler and Spring) add a 6th field for seconds, and some add a 7th for year. This tool uses the standard 5-field format, which is compatible with Unix cron, most cloud providers, and GitHub Actions.
What does * mean in a cron expression?
The asterisk (*) is a wildcard that matches every possible value for that field. For example, *in the hour field means “every hour” (0 through 23). Combined with other specific fields, it lets you create schedules like “every minute of 9 AM” (* 9 * * *).
How do I run a cron job every 5 minutes?
Use the expression */5 * * * *. The */5in the minute field means “every 5th minute” — the task runs at minutes 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, and 55 of every hour. You can use this same pattern with other step values: */10 for every 10 minutes, */15 for every 15 minutes, and so on.
Related Tools
- Unix Timestamp Converter — convert between Unix timestamps and human-readable dates, useful when debugging scheduled jobs.
- Regex Tester — test and debug regular expressions, another pattern-matching tool for developers.