Cron Expressions: Complete Guide for DevOps and Backend Developers

Cron expressions are the universal language for scheduling tasks. Whether you're scheduling database backups, sending reports, or deploying code, you need cron. Here's your complete reference. The 5-Field Format ┌───────────── minute (0-59) │ ┌───────────── hour (0-23) │ │ ┌───────────── day of month (1-31) │ │ │ ┌───────────── month (1-12) │ │ │ │ ┌───────────── day of week (0-6, Sun=0) * * * * * Patterns You'll Use Daily */5 * * * * Every 5 minutes 0 * * * * Every hour (on the hour) 0 0 * * * Daily at midnight 0 9 * * 1-5 Weekdays at 9 AM 0 0 1 * * First of every month 0 0 * * 0 Every Sunday 30 2 * * * Daily at 2:30 AM 0 */4 * * * Every 4 hours 0 9,17 * * * At 9 AM and 5 PM Special Characters Character Meaning Example * Any value * * * * * (every minute) , List 1,15 * * * * (minute 1 and 15) - Range 0 9-17 * * * (9 AM to 5 PM) / Step */10 * * * * (every 10 minutes) L Last 0 0 L * * (last day of month) W Weekday 0 0 15W * * (nearest weekday to 15th) # Nth weekday 0 0 * * 5#2 (2nd Frid