Cron Previous Run Calculator

Look backward from a UTC reference time and list previous matching cron minutes locally.

Cron expression

Reference UTC

Runs

ReadySearches minute-by-minute in UTC with a bounded horizon; the daemon time zone on a real server may differ.

Previous-run recency & staleness audit

Looking backward answers a different operational question: when should the job most recently have fired, how stale is that event, and were the prior intervals consistent?

Freshness threshold (hours)Maximum expected gap (hours)Minimum history span (hours)

—Age of latest expected run

—Median prior gap

—History span

—Recency audit

Ready.

Prior transition	Gap	Within expected gap?	Historical coverage

This checks expected schedule timestamps, not whether a real job completed successfully. Use scheduler logs or monitoring for execution evidence.

Build → explain → project → verify

Treat cron as a deployment configuration: confirm dialect, field count, timezone, day-of-month/day-of-week behavior and several future runs before shipping.