iCloud backs up your iOS devices automatically everyday you have ever enables the automatic iCloud backing up by going to Go to Settings > iCloud > Backup, then turn on iCloud Backup. Also, you can manually create iCloud backup through heading to Settings > iCloud > Backup, then tap Back Up Now.
What if you want to access the iCloud backup file from your PC or simply want to make sure that the iCloud backup has been done? Though you can check the date and size of iCloud backup file on your iPhone by going to Settings > iCloud > Storage > Manage Storage > Backups, you still cannot access the specific data included in it.
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