Cron Expression Generator & Explainer

Generate, validate, and understand cron expressions with our free online tool. Convert complex schedules into human-readable text and get common cron patterns for your job scheduling needs.

Cron Expression Generator

Common Examples:

0 0 * * 0 - Runs every Sunday at midnight
0 0 * * * - Runs every day at midnight
0 * * * * - Runs every hour
* * * * * - Runs every minute
0 0 1 * * - Runs on the first day of every month

Expression Explainer

Enter a cron expression to get a human-readable explanation and see the next execution dates.

Common Examples:

0 0 * * 0 - Runs every Sunday at midnight
0 0 * * * - Runs every day at midnight
0 * * * * - Runs every hour
* * * * * - Runs every minute
0 0 1 * * - Runs on the first day of every month

Understanding Cron Format

Cron expressions are used to schedule recurring jobs and tasks in Unix-like operating systems, Quartz schedulers, and many other platforms. They provide a flexible way to define recurring time patterns for automated tasks.

Cron Format Explained

* * * * * │ │ │ │ │ │ │ │ │ └── Day of week (0-6) (Sunday=0) │ │ │ └──── Month (1-12) │ │ └────── Day of month (1-31) │ └──────── Hour (0-23) └────────── Minute (0-59)

Special Characters in Cron

* - represents all possible values (every minute, every hour, etc.)
, - used to separate multiple values (e.g., "MON,WED,FRI")
- - used to define ranges (e.g., "MON-FRI")
/ - used to specify step values (e.g., "*/15" for every 15 units)
? - used in day-of-month and day-of-week fields to represent "no specific value"
L - represents the last day of the month or last specific day of the week
W - represents the nearest weekday to a given day of the month
# - used to specify the nth day of the month

Common Cron Examples

Time-Based Patterns

* * * * * - Every minute
0 * * * * - Every hour
0 0 * * * - Every day at midnight
*/15 * * * * - Every 15 minutes
0 */2 * * * - Every 2 hours

Day-Based Patterns

0 0 * * MON-FRI - Every weekday at midnight
0 0 1,15 * * - 1st and 15th of every month
0 12 * * MON - Every Monday at noon
0 0 L * * - Last day of every month
0 0 * * SUN - Every Sunday at midnight

Best Practices

Always test your cron expressions before deploying to production
Use descriptive comments to document what each cron job does
Consider time zones when scheduling cron jobs
Avoid scheduling too many jobs at the same time
Use step values (*/15) instead of listing individual times for recurring jobs

Common Use Cases

Database backups and maintenance
Log rotation and cleanup
Sending scheduled reports
Data synchronization tasks
Automated testing and monitoring
Periodic cache clearing
Regular data imports/exports