Crontab cheat sheet
Range Values
Afternoon
# Example of job definition: # .------------------- minute (0 - 59) # | .---------------- hour (0 - 23) # | | .---------- day of month (1 - 31) # | | | .------- month (1 - 12) OR jan,feb,mar,apr ... # | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR mon, tue, wed ... # | | | | | # * * * * * command to be executed * 12-23 * * * /usr/bin/logger "Crontab Afternoon"
Weekdays
# Example of job definition: # .------------------- minute (0 - 59) # | .---------------- hour (0 - 23) # | | .------------- day of month (1 - 31) # | | | .---------- month (1 - 12) OR jan,feb,mar,apr ... # | | | | .------ day of week (0 - 6) (Sunday=0 or 7) OR mon, tue, wed ... # | | | | | # * * * * * command to be executed * * * * 1-5 /usr/bin/logger "Crontab Weekdays"
Winter
# Example of job definition: # .------------------- minute (0 - 59) # | .---------------- hour (0 - 23) # | | .------------- day of month (1 - 31) # | | | .---------- month (1 - 12) OR jan,feb,mar,apr ... # | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR mon, tue, wed ... # | | | | | # * * * * * command to be executed * * * 12-03 * /usr/bin/logger "Crontab Afternoon"
Step Values
Every Minute
# Example of job definition: # .----------------- minute (0 - 59) # | .------------- hour (0 - 23) # | | .---------- day of month (1 - 31) # | | | .------- month (1 - 12) OR jan,feb,mar,apr ... # | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR mon, tue, wed ... # | | | | | # * * * * * command to be executed */1 * * * * /usr/bin/logger "Crontab Every minute"
Every Hour
# Example of job definition: # .---------------- minute (0 - 59) # | .------------- hour (0 - 23) # | | .---------- day of month (1 - 31) # | | | .------- month (1 - 12) OR jan,feb,mar,apr ... # | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR mon, tue, wed ... # | | | | | # * * * * * command to be executed 0 */1 * * * /usr/bin/logger "Crontab Every hour"
Fixed Values
@yearly /usr/bin/logger "Crontab Every Year" @monthly /usr/bin/logger "Crontab Every Month" @weekly /usr/bin/logger "Crontab Every Week" @daily /usr/bin/logger "Crontab Every Day" @hourly /usr/bin/logger "Crontab Every Hour" @reboot /usr/bin/logger "Crontab On Reboot"
Run every weekday of month
Possible examples
| Week | Possible day range | Condition |
|---|---|---|
| 1st | 1-7 | [ $(date +\%d) -le 07 ] |
| 2nd | 8-14 | [ $(date +\%d) -ge 8 ] && [ $(date +\%d) -le 14 ] |
| 3rd | 15-21 | [ $(date +\%d) -ge 15 ] && [ $(date +\%d) -le 21 ] |
| 4th | 22-28 | [ $(date +\%d) -ge 22 ] && [ $(date +\%d) -le 28 ] |
| 5th | 29-31 | [ $(date +\%d) -ge 29 ] |
Examples
1st Monday of month
# Example of job definition: # .---------------- minute (0 - 59) # | .------------- hour (0 - 23) # | | .---------- day of month (1 - 31) # | | | .------- month (1 - 12) OR jan,feb,mar,apr ... # | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR mon, tue, wed ... # | | | | | # * * * * * command to be executed 0 15 * * mon [ $(date +\%d) -le 07 ] && /usr/bin/logger "1st Mon of month 15:00"
2nd Thursday of month
# Example of job definition: # .---------------- minute (0 - 59) # | .------------- hour (0 - 23) # | | .---------- day of month (1 - 31) # | | | .------- month (1 - 12) OR jan,feb,mar,apr ... # | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR mon, tue, wed ... # | | | | | # * * * * * command to be executed 0 15 * * thu [ $(date +\%d) -ge 8 ] && [ $(date +\%d) -le 14 ] && /usr/bin/logger "2nd Thursday of month 15:00"
3rd Wednesday of month
# Example of job definition: # .---------------- minute (0 - 59) # | .------------- hour (0 - 23) # | | .---------- day of month (1 - 31) # | | | .------- month (1 - 12) OR jan,feb,mar,apr ... # | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR mon, tue, wed ... # | | | | | # * * * * * command to be executed 5 03 * * WED [ $(date +\%d) -ge 15 ] && [ $(date +\%d) -le 21 ] && /usr/bin/logger "Test 3rd Wed of month 03:05"
4th Friday of month
# Example of job definition: # .---------------- minute (0 - 59) # | .------------- hour (0 - 23) # | | .---------- day of month (1 - 31) # | | | .------- month (1 - 12) OR jan,feb,mar,apr ... # | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR mon, tue, wed ... # | | | | | # * * * * * command to be executed 5 03 * * fri [ $(date +\%d) -ge 22 ] && [ $(date +\%d) -le 28 ] && /usr/bin/logger "Test 4th Fri of month 03:05"
5th Sunday of month
- Note: This event might not always occur, eg February vs leap year
# Example of job definition: # .---------------- minute (0 - 59) # | .------------- hour (0 - 23) # | | .---------- day of month (1 - 31) # | | | .------- month (1 - 12) OR jan,feb,mar,apr ... # | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR mon, tue, wed ... # | | | | | # * * * * * command to be executed 5 03 * * 7 [ $(date +\%d) -ge 29 ] && /usr/bin/logger "Test 5th Sub of month 03:05"
Reference
https://crontab.guru
https://serverfault.com/questions/986514/crontab-first-wednesday-of-the-month-that-is-followed-by-the-first-monday-of-t
https://stackoverflow.com/questions/58413332/how-to-schedule-a-cron-for-the-first-thursday-of-every-month