Cron Expression Builder
Build a five-field cron expression, validate it, and preview the next runs in your local timezone.
Cron fields are parsed locally in your browser. Nothing is uploaded.
Schedule
Start from a preset, then adjust any field. Fields accept *, lists (1,15), ranges (1-5), and steps (*/15 or 1-5/2).
Expression
0 9 * * *
Every day at 09:00.
Next 5 runs
Times use this device's local timezone. Cron has no timezone field; the server or scheduler applies it.
How to read a cron expression
Five fields from left to right: minute, hour, day of month, month, day of week. An asterisk means every value. When both day fields are restricted, most cron implementations treat the schedule as matching either one, which surprises people; keep one of them as * unless you mean it.
Limits
Cron cannot express "the last weekday of the month" or "every 90 minutes" cleanly. Use a scheduler API for those. DST shifts also move local run times by an hour.