Quick reference
| Setting | Value / behavior |
|---|---|
| Fields | minute hour day month weekday |
| Timezone | UTC |
| Lookahead | up to eight years |
How to use the result
A classic five-field cron expression contains minute, hour, day of month, month and day of week, in that order. This checker supports numeric values, wildcards, comma-separated lists, inclusive ranges and positive steps. For example, */15 9-17 * * 1-5 schedules each quarter-hour between 09:00 and 17:59 on weekdays. Results are calculated in UTC to make the displayed timezone explicit. The tool does not create a scheduled job or contact your server.
Limits and interpretation
When both the day-of-month and day-of-week fields are restricted, this implementation uses the traditional OR rule. Either matching day condition can trigger the schedule. Weekday 0 or 7 means Sunday. It does not support seconds, year fields, named months, named weekdays, ?, L, W, # or macros such as @daily. These extensions vary between schedulers. Confirm the result with the exact cron implementation and timezone used in production, especially around daylight-saving transitions.
Check against your destination
Run the supplied example first, then replace it with a representative input from your own workflow. Change one parameter at a time so the effect is easy to inspect. Copy or download the output and compare it with a small known case before using it in a larger system. A successful calculation establishes only the behavior described on this page; it cannot check the assumptions or access rules of a remote application. Errors are shown next to the workspace rather than silently returning an empty success.
Local processing and data handling
This tool runs in the browser and does not transmit the entered content to a processing service. No input is saved to local storage, added to the URL or synchronized to an account. The clear control removes the current field and displayed result from this page. Clipboard contents and downloaded files remain under your operating system’s control. Keep original inputs when exact byte preservation matters, and avoid including sensitive tokens or private text in screenshots that you later share.
Frequently asked questions
Does the tool contact my server?
No. It processes the provided input locally and does not execute commands on your systems.
Can I download the result?
Yes. Use the Download result control after a successful run.
What happens to my input?
It remains in this page until cleared or closed. It is not saved by the tool.
About this tool
Built and maintained by Mihai at Void Fabric. This page documents the behavior of the current implementation. Found an error or an unclear assumption? Send a reproducible example with sensitive values removed.
Reference: Void Fabric field notes · Testing and editorial policy