OCD users of macOS 10.13.4 rejoice! You can now reorder your Safari bookmarks alphabetically. Instead of having to settle for having Safari’s bookmarks always being in the order you created them, or having to manually drag them into the order you want, you can now have Safari sort them for you.
Why would you want to do this? Well, if you’re browsing through a huge folder of bookmarks, then having any kind of sort order is better than none. And if you’re using accessibility options — for instance if you are using screen readers because your sight is impaired — then alphabetical listings are essential.
How to sort Safari bookmarks alphabetically

Photo: Cult of Mac
This tip applies to your saved bookmarks. To see your saved bookmarks, got to Bookmarks > Edit Bookmarks in the Safari menubar, or type Option-Command-B on the keyboard. This brings up the bookmark page, which contains all your bookmarks, bookmarks folders, and special collections (Favorites, and the Bookmarks Menu). If you right-click on one of your folders, you get options to rename the folder, or two open all its bookmarks in tabs.
But if you’re running the latest version of macOS on your Mac, then you now have a new option when you right-click on bookmarks folder. You can now choose to Sort By to sort bookmarks alphabetically. You can sort either by the bookmark’s name, or by its address (the URL). The latter is good for gathering all bookmarks from a single website together in your list, whatever their page titles may be.
Finally…
It might seem to you that this feature should have been there already. It seems like something that would have shipped a long time ago. And in fact, people have been asking for it for many, many years. According to Mac OS X Hints founder Rob Griffiths, the features was first requested in April 2003 — just three months after Safari first launched on the Mac.
In his investigations, Rob also discovered that there is an upper limit to the number of bookmarks that can be sorted: 450. If you have 450 bookmarks or fewer in a folder, you can sort it using this new option. If you have 451 or more? Tough. The option doesn’t appear in this menu.
Sort bookmarks on an older Mac with SafariSort
If you’re not running High Sierra on your Mac, then you can’t use this new feature. But you can get the same behavior using a free app. It’s called SafariSort, and it does the same thing, only in a blunter manner. To use SafariSort, you just launch the app, and click a button in a pop up window. The app will then sort all your Safari bookmarks at once. There’ no way to do it folder by folder. Still, it seems to work, and if you don’t like it, then you can always upgrade to High Sierra.