0 0 * * * — what this cron expression means

The cron expression 0 0 * * * runs at midnight (00:00) every day. Here is the field-by-field breakdown and what it means in plain English.

Cron expression (minute hour day-of-month month day-of-week)

What 0 0 * * * means

It runs at midnight (00:00) every day.

minute=0, hour=0, day-of-month=*, month=*, day-of-week=*.

Both day fields are *, so it fires every day at exactly 00:00 server time.

The next run is the next time the clock matches: at midnight (00:00) every day.

It runs once a day, at midnight (00:00), every day of the year.

@daily is a shorthand alias that expands to exactly 0 0 * * * — same schedule.