Cron on January 1st at Midnight

The cron expression 0 0 1 1 * schedules a task to run once per year on January 1st at exactly midnight (00:00).

Field-by-field breakdown:

• 0 (Minute): At minute 0. The task fires at the top of the hour.
• 0 (Hour): At hour 0 (midnight / 12 AM). The task runs at the very start of the new year.
• 1 (Day of Month): On the 1st day of the month only.
• 1 (Month): In January only. The month field restricts execution to the first month of the year.
• * (Day of Week): Every day of the week. No restriction on the day of the week, as the date is already fully specified.

This means your task will execute exactly once per year, at the stroke of midnight on January 1st. This is the most common schedule for annual tasks that need to align with the calendar year boundary. It is perfect for archiving the previous year's data, resetting annual counters, rotating annual encryption keys, or generating year-end reports. Be aware that January 1st midnight is often a high-traffic time for systems processing New Year's events, so ensure your task can handle potential resource contention. Consider scheduling slightly later (e.g., 1 AM or 2 AM) if midnight congestion is a concern. This expression is supported by standard cron on Linux/macOS, as well as cloud services like AWS CloudWatch, Google Cloud Scheduler, and GitHub Actions.