Cron Generator
Choose a schedule pattern and configure its interval, time, weekdays, or day of month.
- 1.Select a schedule type.
- 2.Adjust the available controls.
- 3.Review and copy the generated expression.
Documentation
CronTools Documentation
A practical guide to building, understanding, testing, and previewing standard Linux cron schedules.
Quick start
CronTools works without an account. Start with the Generator when you know the schedule you want, or the Explainer when you already have an expression.
*/15 9-17 * * 1-5
│ │ │ │ └─ Monday-Friday
│ │ │ └── Every month
│ │ └──── Every day of month
│ └───────── 9 AM through 5 PM
└─────────────── Every 15 minutesTool guides
Cron Explainer
Translate a Linux five-field expression into plain English and inspect each field.
- 1.Paste or type an expression.
- 2.Read the live explanation.
- 3.Check the field breakdown for details.
Cron Validator
Check structure, field ranges, lists, ranges, and step syntax before deployment.
- 1.Enter an expression.
- 2.Review the validity status.
- 3.Use field-level suggestions to correct errors.
Next Run Calculator
Calculate upcoming executions in a selected IANA timezone with a live countdown.
- 1.Enter a valid expression.
- 2.Choose a timezone.
- 3.Review the next run and upcoming schedule.
Cron Playground
Use validation, explanation, next runs, presets, and schedule preview in one workspace.
- 1.Start with an expression or preset.
- 2.Inspect all live panels.
- 3.Copy the expression or explanation.
Supported syntax
Five fields
Minute, hour, day of month, month, and day of week.
Operators
Wildcards, lists, ranges, steps, and range steps.
Runs locally
Expressions are processed in your browser and are not saved to an application database.
Current limitations
CronTools currently targets standard Linux five-field cron. Quartz expressions, Jenkins H syntax, and AWS EventBridge schedules have different rules and should be checked against their platform documentation.