Min Hour Day Mon Weekday
* * * * * command to be executed
┬ ┬ ┬ ┬ ┬
│ │ │ │ └─ Weekday (0=Sun .. 6=Sat)
│ │ │ └────── Month (1..12)
│ │ └─────────── Day (1..31)
│ └──────────────── Hour (0..23)
└───────────────────── Minute (0..59)
Operators
| Operator |
Description |
* |
all values |
, |
separate individual values |
- |
a range of values |
/ |
divide a value into steps |
Examples
| Example |
Description |
0 * * * * |
every hour |
*/15 * * * * |
every 15 mins |
0 */2 * * * |
every 2 hours |
0 18 * * 0-6 |
every week Mon-Sat at 6pm |
10 2 * * 6,7 |
every Sat and Thu on 2:10am |
0 0 * * 0 |
every Sunday midnight |
@reboot |
every reboot |
Crontab
# Adding tasks easily
echo "@reboot echo hi" | crontab
# Open in editor
crontab -e
# List tasks
crontab -l [-u user]