Cron式チェッカー
Cron式を入力すると次回実行時刻と直近のスケジュールを確認できます。GitHub ActionsやLinux Cronの設定に。
Parse cron expressions and preview upcoming execution times.
GitHub Actions用（UTC換算）
Cron Expression Cheat Sheet
| Expression | Meaning |
|---|---|
| * * * * * | Every minute |
| 0 * * * * | Every hour at :00 |
| 0 9 * * * | Every day at 9:00 AM (UTC) |
| 0 9 * * 1 | Every Monday at 9:00 AM |
| 0 0 1 * * | First day of every month at midnight |
| */5 * * * * | Every 5 minutes |
| 0 9-17 * * 1-5 | Every hour 9am–5pm, Mon–Fri |
┌──── minute (0–59)
│ ┌──── hour (0–23)
│ │ ┌──── day of month (1–31)
│ │ │ ┌──── month (1–12)
│ │ │ │ ┌──── day of week (0–7, 0/7 = Sunday)
* * * * *
FAQ
Q: What is a cron expression?
A: A cron expression is a string of 5 fields that defines a repeating schedule. It is used in Linux crontab, GitHub Actions, and many scheduling systems.
Q: How do I run a cron job every 5 minutes?
A: Use */5 * * * *
Q: What does 0 0 * * * mean?
A: Every day at midnight (00:00 UTC).
Q: Is there a difference between Linux cron and GitHub Actions cron?
A: The syntax is the same, but GitHub Actions always uses UTC. Linux cron uses the server's local timezone.
Q: How do I validate my cron expression?
A: Enter it in the checker above — it shows the next 10 scheduled execution times instantly.