Cron Expression Parser
Parse cron expressions into human-readable descriptions. See when your cron job will run next.
Presets:
Understanding Cron Expressions — The Complete Crontab Syntax Guide
Cron expressions are the scheduling language used by Unix/Linux cron daemons, Kubernetes CronJobs, AWS CloudWatch Events, GitHub Actions, CI/CD pipelines, and countless task schedulers. A standard cron expression consists of 5 fields separated by spaces: minute hour day-of-month month day-of-week.
Cron Field Reference
- Minute (0—59) — Which minute of the hour the job runs
- Hour (0—23) — Which hour of the day (24-hour format)
- Day of Month (1—31) — Which day of the month
- Month (1—12 or JAN—DEC) — Which month of the year
- Day of Week (0—6 or SUN—SAT) — Which day of the week (0 = Sunday)
Cron Special Characters and Operators
*— Any value. Matches every possible value for that field.*/n— Step value. Runs every n intervals (e.g.,*/5in minute = every 5 minutes).1,3,5— List. Runs at specific values (e.g.,1,15in day = 1st and 15th).1-5— Range. Runs for every value in the range (e.g.,1-5in day-of-week = Monday through Friday).
Common Cron Schedule Examples
* * * * *— Every minute (useful for testing, not recommended in production)*/5 * * * *— Every 5 minutes (health checks, monitoring)0 * * * *— Every hour at minute 0 (log rotation, cache clearing)0 0 * * *— Daily at midnight (database backups, report generation)0 9 * * 1-5— Weekdays at 9:00 AM (business-hours notifications)0 0 1 * *— First day of every month at midnight (billing, monthly reports)0 2 * * 0— Every Sunday at 2:00 AM (weekly maintenance window)
Where Cron Expressions Are Used
- Linux/Unix crontab — The original cron scheduler (
crontab -e) - Kubernetes CronJobs — Schedule containerized batch jobs in K8s clusters
- GitHub Actions —
scheduletrigger in workflow YAML files - AWS CloudWatch Events / EventBridge — Trigger Lambda functions on a schedule
- CI/CD pipelines — Jenkins, GitLab CI, CircleCI all support cron scheduling
- Database maintenance — pg_cron for PostgreSQL, MySQL Event Scheduler
Frequently Asked Questions
This tool supports the standard 5-field UNIX cron syntax: minute (0-59), hour (0-23), day of month (1-31), month (1-12), and day of week (0-7). It handles wildcards (*), ranges (1-5), steps (*/15), lists (1,3,5), and combinations like 0 9-17 * * 1-5 (every hour during business hours on weekdays).
Yes. The parser calculates and displays the next 5 scheduled run times based on your current local time. This helps you verify that your cron expression matches the schedule you intend before deploying it to a server.
The step syntax */5 means "every 5th value starting from 0" and is equivalent to 0,5,10,15,20,25,30,35,40,45,50,55 for the minute field. The list syntax 0,5,10,15 runs only at those specific values. Use */5 for regular intervals and explicit lists for specific times.
No. The cron expression is parsed and evaluated entirely in your browser using JavaScript. No data is transmitted to any server. This makes it safe to test cron schedules for internal systems without exposing your infrastructure details.
This parser supports the standard 5-field cron format used by crontab, most Linux systems, and cloud schedulers like AWS CloudWatch and GitHub Actions. Extended 6-field (with seconds) or 7-field (with year) formats used by Quartz or Spring are not supported.