Cron Explainer | How to use and interpret results
Read a five-field cron expression as minute, hour, day, month and weekday parts. The explanation expands familiar stars, steps, ranges and lists to help inspect a configuration.
- Runs in your browser
- Nothing is uploaded
- No signup; device limits apply
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How to use this tool
Paste five space-separated fields without a command or seconds field. Verify the actual scheduler dialect and time zone in the server configuration separately.
Results and examples
*/15 9-18 * * 1-5 displays a 15-minute step, hours 9 through 18 and Monday through Friday. It is a field explanation, not a computed list of upcoming runs.
Worked example
*/15 9-18 * * 1-5 displays a 15-minute step, hours 9 through 18 and Monday through Friday. It is a field explanation, not a computed list of upcoming runs.
Limitations
- Numeric ranges are not exhaustively validated and runs are not simulated.
- The scheduler's combined day-of-month and weekday semantics are not evaluated.
Fields
| Field | Guidance and constraints |
|---|---|
| 5-field Cron | Check the unit and format displayed beside this field. |
Data handling
Processing stays in the current browser tab; the site does not upload tool input for the calculation itself.
Sources
Frequently asked questions
How is a 15-minute expression described?
*/15 9-18 * * 1-5 displays a 15-minute step, hours 9 through 18 and Monday through Friday. It is a field explanation, not a computed list of upcoming runs.
Does an explanation prove the schedule is valid?
Numeric ranges are not exhaustively validated and runs are not simulated. The scheduler's combined day-of-month and weekday semantics are not evaluated.
