Key Features
Full Vixie-cron syntax: steps, ranges, lists, named months and weekdays
Plain-English description of exactly when the schedule fires
Next 5 run times computed in your local timezone
@daily, @hourly, @weekly, @monthly, and @yearly shortcut support
Correct dom/dow OR-rule semantics ("0 0 1 * 1" fires the 1st AND Mondays)
Detects impossible schedules like February 30th that can never fire
How to Use
1Type or paste a 5-field cron expression (or click a preset)
2Read the plain-English translation of the schedule
3Check the next 5 run times against your expectations
4Copy the description into docs, tickets, or PR reviews
Common Use Cases
Understand a cron line in a legacy crontab before editing it
Verify a GitHub Actions schedule fires when you actually expect
Debug "why did my job not run?" by previewing the next occurrences
Learn cron syntax interactively with common presets
Frequently Asked Questions
What are the five fields in a cron expression?
Minute (0–59), hour (0–23), day of month (1–31), month (1–12), and day of week (0–7, where 0 and 7 are both Sunday) — in that order.
Why does "0 0 1 * 1" run on Mondays too?
Standard cron uses an OR rule when both day-of-month and day-of-week are restricted: the job fires if either matches. This tool implements the exact Vixie-cron semantics.
Does this support 6-field cron with seconds?
No — this explains the standard 5-field format used by crontab, GitHub Actions, and most cloud schedulers. Six-field dialects (Quartz, AWS EventBridge) are rejected with a clear message.
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