How to Back up your Photos library
Find your photos
By default, your photo library lives in your user account’s Pictures folder. So, it’ll be in /Macintosh HD/ Users/[your username]/Pictures. It’s a package, not a folder — meaning it appears like one file, but isn’t really.
Drag to a drive
If you want to back up your entire Photos library, drag and drop it to a location on an external drive. Don’t use a USB flash drive/memory stick — they’re often too low in capacity and, though portable, are too easy to lose.
Set a schedule
One of Carbon Copy Cloner’s best features is its scheduler, which doesn’t just schedule backups but also lets you wake your Mac if it’s asleep, or defer a backup if something is using the same destination at that time.
Open it up
To see the package’s contents, Ctrl–click it and choose Show Package Contents. You should see the structure shown here. The actual photographs are stored under Masters and then organized by year and month.
If you want to automatically backup your photo library, we suggest using a dedicated backup app, such as the popular Carbon Copy Cloner. This app is free for 30 days, so you can try out all of its features.
Say where to go
We’ve set our source and our backup schedule. Now to choose our backup’s destination. Backing up to the same drive is a bad idea — hard disks can and do fail. Here we’ve attached and selected an external SSD.
If you might open backups in an app other than Photos, check which file formats that app can open. Since iOS 11 and High Sierra, some of your pictures may be stored as HEIF (High Efficiency Image File Format), not JPEG.
Select the source
We’d recommend backing up everything that’s important, of course, and Carbon Copy Cloner can do exactly that. Here, though, we’re concentrating on our Photos library; once again we’re selecting it from our Pictures folder.
Set it off
If your Photos library is enormous this would be a good time to go and make a cup of coffee — backing up gigabytes of data is slow even on speedy external drives. This is why automation is such a great idea.