Cron Expression Parser: Next Run Times in KST and UTC
Explains a 5-field cron expression and lists the next 10 run times in Korea Standard Time (KST) and UTC, with the equivalent expression for a server running on UTC.
How to use
- Type the cron expression as minute hour day-of-month month day-of-week, or tap a preset such as Every 5 min or Weekdays 22:00.
- The field table shows how each field was read. Nicknames such as @daily and names such as mon or jan are accepted.
- Change the start time (default: now, in KST) to list the next 10 run times in KST and UTC.
- If your server runs on UTC, use the 'On a UTC server' expression, and copy everything with the copy button.
FAQ
What happens when both day-of-month and day-of-week are set?
If neither field is *, the job runs when either one matches. 30 4 1,15 * 5 runs at 04:30 on the 1st, the 15th, and every Friday. If one field is *, only the other applies. A field that starts with * such as */2 makes both conditions required. This follows the crontab(5) man page and Vixie cron.
How do I write every 5 minutes or every minute?
Every 5 minutes is */5 * * * * and every minute is * * * * *. Hourly is 0 * * * * and weekdays at 22:00 is 0 22 * * 1-5. The preset buttons fill these in.
My server is on UTC but I want 9:00 Korea time.
KST is 9 hours ahead of UTC, so subtract 9 from the hour: 9:00 KST every day is 0 0 * * * in UTC. Hours 0 to 8 in KST fall on the previous day in UTC, so day-of-month and day-of-week must shift by one day too; this tool does that. Expressions with a month set, or the 1st of the month before 09:00 KST, cannot be written as one UTC expression, so read the UTC column in the run list instead.
What is the difference between 0, 7 and sun in day-of-week?
None; all mean Sunday. Day-of-week takes 0-7 (0 and 7 are Sunday) or sun-sat, month takes 1-12 or jan-dec. Names are case-insensitive.
How are */23 and 0-23/2 read?
A step /n skips n values inside the range. 0-23/2 in the hour field means the even hours 0, 2, ... 22. */23 in the hour field means hours 0 and 23 only, not every 23 hours, because the count restarts at 0 each day.
Which syntax is not supported?
Only the standard 5 fields and the nicknames @yearly, @annually, @monthly, @weekly, @daily and @hourly are read. Seconds or year fields, extensions such as ?, L and # (Quartz, AWS), @reboot, and a bare 5/10 are reported as errors. The time zone is fixed to KST, which has no daylight saving.
AI agents: this calculation is available over an API without the form — see /llms.txt and the tool list at /api/calc; confirm the final result on this page.