What does a cron expression describe?

A cron expression specifies when a recurring task runs using minute, hour, day-of-month, month, and day-of-week fields.

Can I validate an existing expression?

Yes. Enter an expression to check its syntax and view the schedule interpretation before using it in a scheduler.

Does cron syntax work everywhere?

Not exactly. Traditional Unix cron, Quartz, and hosted schedulers can differ in field count and special tokens; confirm the target scheduler's dialect.

Cron Expression Builder

Build and validate cron expressions with an intuitive interface

Build Expression

Minute (0-59)

* = every min
*/15 = every 15 min
0,30 = 0 & 30

Hour (0-23)

* = every hour
*/6 = every 6 hrs
9-17 = 9 AM to 5 PM

Day (1-31)

* = every day
1 = 1st of mo
1,15 = 1st & 15th

Month (1-12)

* = every month
1-6 = Jan to Jun
12 = Dec only

Weekday (0-6)

* = every day
1-5 = Mon to Fri
0,6 = weekends

Common Patterns:

* = every value

*/n = every n units

a-b = range from a to b

a,b,c = specific values

Expression & Status

Expression

Cron Format Reference

Field Order:

* * * * *

│ │ │ │ │

│ │ │ │ └─ Day of week (0-6)

│ │ │ └─── Month (1-12)

│ │ └───── Day of mo (1-31)

│ └─────── Hour (0-23)

└───────── Minute (0-59)

Special Characters:

* - Any value

, - List separator

- - Range

/ - Step values

GitHub Actions YAML Without Memorizing the Schema

The structure of a workflow file, why `on:` becomes a YAML boolean (and how to dodge it), and the common triggers you'll reach for first when bootstrapping CI/CD.