The cron expression for every weekday (Monday through Friday)
0 0 * * 1-5
The day-of-week range 1-5 covers Monday (1) through Friday (5). The job fires at midnight every weekday — five runs per week. Most schedulers also accept name aliases: 0 0 * * MON-FRI is equivalent.
See the dedicated guide for the full breakdown: Cron every day.
Paste it into the editor above to see the next runs on a calendar.