By default how often does Window automatically defrag a magnetic hard drive?

By default, Windows automatically defragments magnetic hard drives once a week. The system schedules this task to optimize disk performance by rearranging fragmented data for more efficient access. Users can adjust the schedule or manually initiate defragmentation through the Disk Defragmenter tool in Windows. SSDs, however, are not defragmented as frequently, as they use a different optimization method called TRIM.