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José David Baena
Tools and working references

Background jobs / Schedule explorer

Scheduled Job & Overlap Explorer

When will this schedule fire, and what happens if a run is still active or earlier ticks were missed?

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Croner 10.0.1 / numeric five-field cron / DOM-DOW OR

No seconds, macros, names, or calendar extensions. The engine only enumerates dates here: it is paused, has no callback, and never executes jobs. Actual run policies are a separate illustration below.

Choose a schedule and a planning policy

Choose a schedule and a planning policy

minute hour day-of-month month weekday; numbers, *, comma lists, ranges, and / steps.

Examples: UTC, America/New_York, Europe/London, Australia/Lord_Howe.

This input is UTC, not the selected local timezone. Also used as the modeled resume instant.

Constant duration for overlap calculations.

A supplied count before the resume instant, not inferred from an outage or this cron expression.

Calendar occurrences

After 2026-09-07T09:00:00.000Z, within 366 UTC days. Timestamps are planned occurrences, not delivery guarantees.

Next 8 occurrences under the pinned profile
UTC instantWall clock (UTC)DST and offset notes
2026-09-07T09:15:00.000Z2026-09-07 09:15 GMT+0No boundary flagged at this occurrence
2026-09-07T09:30:00.000Z2026-09-07 09:30 GMT+0No boundary flagged at this occurrence
2026-09-07T09:45:00.000Z2026-09-07 09:45 GMT+0No boundary flagged at this occurrence
2026-09-07T10:00:00.000Z2026-09-07 10:00 GMT+0No boundary flagged at this occurrence
2026-09-07T10:15:00.000Z2026-09-07 10:15 GMT+0No boundary flagged at this occurrence
2026-09-07T10:30:00.000Z2026-09-07 10:30 GMT+0No boundary flagged at this occurrence
2026-09-07T10:45:00.000Z2026-09-07 10:45 GMT+0No boundary flagged at this occurrence
2026-09-07T11:00:00.000Z2026-09-07 11:00 GMT+0No boundary flagged at this occurrence

Verify DST rules in your actual scheduler. In the supplied New York examples, this pinned engine enumerates 03:30 for the spring's nonexistent 02:30 slot and the first 01:30 during the autumn repeated hour. Other schedulers may skip or repeat differently.

Modeled run policies

Catch-up offers each supplied missed tick at the resume instant; coalescing offers one. The overlap policy then allows, skips, or serializes those offers and future ticks. Combining catch-up with overlap-skip can suppress all but the first simultaneous catch-up offer.

Modeled peak concurrency

1

Maximum modeled queue delay

35 min

Overlap-skipped offers

0

Missed ticks omitted / coalesced

0 / 0

Policy effects, not operations performed

Illustrated starts and finishes; no jobs execute
OfferDue (UTC)Start / finish (UTC)Policy outcome
tick-12026-09-07T09:15:00.000Z
2026-09-07T09:15:00.000Z
2026-09-07T09:35:00.000Z
starts; delay 0 s
tick-22026-09-07T09:30:00.000Z
2026-09-07T09:35:00.000Z
2026-09-07T09:55:00.000Z
queued; delay 5 min
tick-32026-09-07T09:45:00.000Z
2026-09-07T09:55:00.000Z
2026-09-07T10:15:00.000Z
queued; delay 10 min
tick-42026-09-07T10:00:00.000Z
2026-09-07T10:15:00.000Z
2026-09-07T10:35:00.000Z
queued; delay 15 min
tick-52026-09-07T10:15:00.000Z
2026-09-07T10:35:00.000Z
2026-09-07T10:55:00.000Z
queued; delay 20 min
tick-62026-09-07T10:30:00.000Z
2026-09-07T10:55:00.000Z
2026-09-07T11:15:00.000Z
queued; delay 25 min
tick-72026-09-07T10:45:00.000Z
2026-09-07T11:15:00.000Z
2026-09-07T11:35:00.000Z
queued; delay 30 min
tick-82026-09-07T11:00:00.000Z
2026-09-07T11:35:00.000Z
2026-09-07T11:55:00.000Z
queued; delay 35 min

Assumptions and limits

  • The start boundary is exclusive. Up to eight future occurrences are shown within 366 UTC days.
  • Only numeric five-field expressions are accepted: minute, hour, day, month, weekday. Sunday is 0 or 7; day-of-month and weekday use OR.
  • Enumeration follows the pinned engine and the runtime's IANA timezone database, not a guarantee about another scheduler.
  • Overlap and missed-run policies are a separate deterministic planning model, not Croner execution settings.
  • Missed ticks are a hypothetical count offered at the selected resume time, not an inferred outage history.
  • Run duration is constant; startup delays, distributed locks, retries, failures, and resource contention are not modeled.