Cron Twice Daily on Weekdays (8 AM and 8 PM)

The cron expression 0 8,20 * * 1-5 schedules a task to run twice per weekday, at 8:00 AM and 8:00 PM, Monday through Friday.

Field-by-field breakdown:

• 0 (Minute): At minute 0. The task fires at the top of each qualifying hour.
• 8,20 (Hour): At hours 8 (8 AM) and 20 (8 PM). The list notation creates a symmetrical 12-hours-apart schedule with one morning and one evening execution.
• * (Day of Month): Every day from 1 through 31. No restriction on the day of the month.
• * (Month): Every month from January through December. No restriction on which month.
• 1-5 (Day of Week): Monday through Friday. The range covers all five business days.

This means your task will execute 10 times per week: twice per day on each of five weekdays. The 12-hour spacing between 8 AM and 8 PM creates a balanced rhythm that covers both the morning preparation window and the evening wrap-up window. The 8 AM run can prepare systems for the business day ahead, while the 8 PM run can process the day's accumulated data and prepare overnight reports. This pattern is more frequent than daily but less aggressive than hourly, making it suitable for medium-priority synchronization and reporting tasks. This expression is supported by standard cron on Linux/macOS, as well as cloud services like AWS CloudWatch, Google Cloud Scheduler, and GitHub Actions.