Input
Preparing your workspace…
How to use
- Enter a five-field expression or choose a common schedule.
- Set the reference time and time zone.
- Inspect the meaning, fields and next runs; copy the expression or download JSON.
Reading a five-field Cron schedule
The five fields describe minute, hour, day of month, month and day of week. They select matching calendar times rather than measuring a fixed interval since the previous run.
The explanation and next-run preview help check a schedule before installing it. The expression is parsed locally; opening this page does not create a job or run a command.
Supported expression syntax
Use the standard five-field layout without a seconds field. Lists, ranges, steps and supported month/weekday names can be combined; Quartz-specific extensions and macros are not accepted.
0 9 * * MON-FRI
2026-01-01 09:00 · UTC2026-01-02T09:00:00ZA fixed example; the time zone and precision are part of the calculation.
Matching days and time zones
When day of month and day of week are both restricted, either matching day is accepted. Runs are searched strictly after the reference time using the selected zone, so inspect DST boundaries for schedules near a clock change.
Using the preview
The next-run search is bounded to ten years and up to 50 requested dates. A sparse schedule can yield fewer runs. Copy the expression for your scheduler or download JSON to retain the field breakdown and preview.
ISO calendar dates, nanosecond precision and explicit time zones. Cron uses five fields, up to 50 runs within 10 years, reference years 1900–2199 and a 5-second processing limit. Time-zone data comes from your browser. Processing stays on your device.
Frequently asked questions
Does this support Quartz or six fields?
No. Use five fields without seconds. Macros and the L, W, #, ?, H extensions are not supported.
Why does */40 not mean every 40 elapsed minutes?
The minute field restarts each hour. It matches minute 0 and minute 40 of each eligible hour rather than a continuous interval.
How are day of month and day of week combined?
When both fields are restricted, a match in either field qualifies. Check the displayed day-matching note and upcoming dates.
What if a schedule has no upcoming dates?
The search stops at ten years. Invalid schedules report an error; sparse valid schedules can produce fewer dates than requested.
Does the expression include the chosen time zone?
No. The zone is used for this preview. Configure the corresponding time zone separately in the destination scheduler.