# CRON expressions

Azure Functions uses the NCronTab library to interpret CRON expressions. A CRON expression includes six fields:

`{second} {minute} {hour} {day} {month} {day-of-week}`

Each field can have one of the following types of values:

```
Type Example When triggered
A specific value 0 5 * * * * at hh:05:00 where hh is every hour
(once an hour)
All values (*) 0 * 5 * * * at 5:mm:00 every day, where mm is
every minute of the hour (60 times
a day)
A range (- operator) 5-7 * * * * * at hh:mm:05,hh:mm:06, and hh:mm:07
where hh:mm is every minute of every
hour (3 times a minute)
A set of values (, operator) 5,8,10 * * * * * at hh:mm:05, hh:mm:08, and hh:mm:10
where hh:mm is every minute of every
hour (3 times a minute)
An interval value (/ operator) 0 */5 * * * * at hh:05:00, hh:10:00, hh:15:00, and
so on through hh:55:00 where hh is
every hour (12 times an hour)
```

Refs.:

https://docs.microsoft.com/en-us/azure/azure-functions/functions-bindings-timer#cron-expressions