How To Read Cron Expressions

The five fields

Classic Unix cron has five fields, left to right: minute, hour, day of month, month, day of week. Each field has a fixed value range.

The six-field variant (Quartz)

Special characters

Shortcut strings

Day of month vs. day of week

Day of week numbering

Time zones

Reading an expression aloud

Common real-world patterns

Special extensions

Common mistakes

Run the numbers