Cron Expression Generator

Cron Syntax

A cron expression has 5 fields:

minute  hour  day-of-month  month  day-of-week

• * — any value
• */5 — every 5 units
• 1-5 — a range (Mon–Fri)
• 0,15,30 — a list

Test your expression in a terminal with: crontab -e. Some systems use a 6th field (seconds) or support macros like @daily.