Cron Expression
0 0 1 1,7 *
Cron Expression: Cron Every 6 Months
Learn how to create a cron expression for 'cron every 6 months'. Runs January 1st and July 1st at midnight with our free generator tool.
Expression Breakdown
0
Minute(0-59)
0
Hour(0-23)
1
Day(1-31)
1,7
Month(1-12)
*
Weekday(0-6)
| Field | Value | Meaning |
|---|---|---|
| Minute | 0 | At minute 0 |
| Hour | 0 | At hour 0 |
| Day of Month | 1 | Day 1 |
| Month | 1,7 | Months 1,7 |
| Day of Week | * | Any day of the week |
This cron expression represents: cron every 6 months
Cron Expression
0 0 1 1,7 *
What This Expression Does
Runs twice per year: at midnight on January 1st and July 1st. The 1,7 list in the month field selects January and July, and the 1 in the day-of-month field pins the run to the first of each.
Use Cases
Semi-annual jobs tend to be housekeeping with a long horizon:
- Rotating API keys, SSH keys, or service credentials on a 6-month policy
- Pruning soft-deleted records past their retention window
- Half-year data archival to cold storage
- Scheduled reminders for security reviews or dependency audits
How to Use
- Copy the cron expression above
- Open your crontab with
crontab -e - Add a new line with:
0 0 1 1,7 * /path/to/your/script.sh - Save and exit
Why Not */6 in the Month Field?
0 0 1 */6 * looks like “every 6 months” but the step starts at month 1, selecting January and July — the same as 1,7, so it happens to work. The list form is preferred because it’s explicit: change it to 4,10 and you instantly have an April/October cycle, no step arithmetic required.
Alternative Formats
-
Different anchor months:
0 0 1 3,9 *runs March 1st and September 1st -
Mid-month runs:
0 0 15 1,7 *runs January 15th and July 15th -
With failure alerting:
0 0 1 1,7 * /path/to/script.sh || mail -s "Semi-annual job failed" admin@example.com