Cron expression explainer — plain-language schedule and next run times
Checks whether a server cron job, GitHub Actions schedule, or Spring @Scheduled expression is written correctly. Errors tell you which field is wrong and why.
The file is never sent to a server — processed entirely in this browser
5 fields: minute hour day month weekday · 6 fields: second minute hour day month weekday · Shorthand like @daily, @hourly also works
Field breakdown
| Field | Input | That value |
|---|---|---|
| 분 | 0 | 0 |
| 시 | 9 | 9 |
| 일 | * | All |
| 월 | * | All |
| 요일 | 1-5 | 월, 화, 수, 목, 금 |
Next run time (KST)
Calculating…
Cron syntax cheat sheet
| * | 모든 값 |
|---|---|
| 5 | 그 값 (예: 분 5 → 5분) |
| 1-5 | 범위 (요일 1-5 → 월~금) |
| 1,15 | 목록 (일 1,15 → 1일과 15일) |
| */10 | 간격 (분 */10 → 10분마다) |
| 8-18/2 | 범위 안에서 간격 |
| MON-FRI, JAN | 요일·월 영문 약자 |
| 0 또는 7 | 일요일 |
Ranges: second/minute 0–59, hour 0–23, day 1–31, month 1–12, weekday 0–7. If your server or GitHub Actions runs on UTC, subtract 9 hours from KST before entering it.
Advertisement
How to use Cron expression breakdown
- 1Enter a cron expression, or click an example.
- 2See a plain-language explanation and a breakdown of each field (minute, hour, day, month, weekday).
- 3Shows the next 10 run times in KST.
Frequently asked questions
What if I specify both the day and the weekday?
Standard cron runs when either condition matches (OR logic). E.g. 0 0 1 * 1 runs both on the 1st of every month and every Monday.
What if the server's clock is set to UTC?
Cron runs on the server's own time zone. If the server uses UTC, 9 AM KST must be written 9 hours earlier, like 0 0 * * *. GitHub Actions also runs on UTC.
Do L, W, # work too?
Quartz extended syntax (L, W, #) isn't supported yet.
Advertisement