Mode
Quick Presets
Configure Fields
Minute
0-59
Hour
0-23
Day of Month
1-31
Month
1-12
Day of Week
0-6 (Sun-Sat)
Cron Expression
* * * * ******What this cron does:
Every minute
Next Scheduled Runs
Cron Syntax Quick Reference
Field Order
┌───────────── minute (0 - 59)
│ ┌───────────── hour (0 - 23)
│ │ ┌───────────── day of month (1 - 31)
│ │ │ ┌───────────── month (1 - 12)
│ │ │ │ ┌───────────── day of week (0 - 6)
* * * * *Special Characters
*- Any value,- Value list (1,3,5)-- Range (1-5)/- Step values (*/15)
Privacy Guaranteed
All cron expression building and parsing happens entirely in your browser. No data is sent to any server.
About Cron Expression Builder
Build and parse cron expressions with our free online cron builder. Use the visual interface to create cron schedules by selecting minutes, hours, days, months, and weekdays. Supports all cron syntax including wildcards (*), ranges (1-5), lists (1,3,5), and step values (*/15). Parse existing cron expressions to see human-readable explanations. Preview the next 5 scheduled run times. Choose from common presets like "Every minute", "Daily at midnight", "Weekdays at 9 AM", and more. All processing happens locally in your browser - your data never leaves your device.
Understanding Cron Syntax
┌───────────── minute (0 - 59) │ ┌───────────── hour (0 - 23) │ │ ┌───────────── day of month (1 - 31) │ │ │ ┌───────────── month (1 - 12) │ │ │ │ ┌───────────── day of week (0 - 6) (Sunday = 0) │ │ │ │ │ * * * * *
Special Characters
*Wildcard (Any)
Matches any value. Example: * * * * * runs every minute.
,List
Specifies multiple values. Example: 0 9,17 * * * runs at 9 AM and 5 PM.
-Range
Specifies a range. Example: 0 9-17 * * * runs every hour from 9 AM to 5 PM.
/Step
Specifies increments. Example: */15 * * * * runs every 15 minutes.
Common Examples
| Expression | Description |
|---|---|
| * * * * * | Every minute |
| 0 * * * * | Every hour (at minute 0) |
| 0 0 * * * | Daily at midnight |
| 0 9 * * 1-5 | Weekdays at 9:00 AM |
| 0 0 1 * * | Monthly on the 1st at midnight |
| 0 0 1 1 * | Yearly on January 1st |
Where Cron is Used
- Linux/Unix crontab - Schedule system tasks and maintenance scripts
- CI/CD pipelines - GitHub Actions, GitLab CI, Jenkins scheduled builds
- Cloud services - AWS CloudWatch Events, Google Cloud Scheduler, Azure Functions
- Task queues - Celery Beat, Bull, Agenda.js for Node.js applications
- Kubernetes - CronJobs for scheduled container workloads
Frequently Asked Questions
What is a cron expression?
A cron expression is a string of five (or six) fields separated by spaces that represents a schedule. The standard format is: minute (0-59), hour (0-23), day of month (1-31), month (1-12), day of week (0-6, where 0 is Sunday).
What special characters can I use?
Cron supports several special characters: * (any value), , (list separator, e.g., 1,3,5), - (range, e.g., 1-5), / (step values, e.g., */15 means every 15).
How do day of month and day of week work together?
In standard cron, if both day of month and day of week are specified (not *), the job runs when EITHER condition is met (OR logic). If only one is specified, only that field is considered.
Is my cron expression data safe?
Yes! All cron expression building and parsing happens entirely in your browser using JavaScript. No data is ever sent to any server, ensuring complete privacy.
How accurate are the next run predictions?
The next run times are calculated based on your local system time and timezone. Actual execution depends on your server's timezone configuration.