The (paid) Professional version lets you create a library of as many fonts as you want. Free version is limited to 2500 fonts, which is still a good amount.

Beside grouping by storage folder, you can create your own groups of fonts. For example for clients or projects.

Create tags to identify and organize your fonts.

You can customize your view so that you can arrange the "Information" panel with all the technical details of the font, e.g. no. of glyphs/characters (often different!), all OpenType features in the selected font, exact location of the font file, etc.

Click the X_2 button and enable/disable OpenType features of the selected font in the sample window with a customizable text preview.

Most features of the paid Standard and Professional versions are available in the Free version. The main difference is the number of fonts allowed in the library (2500 vs. 10,000 in Standard and unlimited in Professional).

No subscription software that you don't own. How many utilities, plug-ins, suites, and so on do you have to subscribe to?

Fonts don't have to be installed for use, you can also load them. This way they're available for use in all programs, but won't stay 'installed' after a reboot.

Any folder, including mapped network folders, can be checked for fonts that are added to the font library.

Very good support, which usually reacts extremely quickly when something goes wrong. So far there has been nothing unresolved.

MainType easily allows you to view all the special characters and glyphs available in a font and copy and paste them into other programs. Definitely the easiest font manager to do this!

You know that there's always too little space. You can customize your "view" so that on the second monitor you can see a big window only with the glyphs of the selected font in the main window.

It's easy to create a number of different font sample sheets to include in style guides or create your own font book.

All the organization of the panels is simple, clear, easy to change and adapt to everyone needs. Simply a great interface with everything is easy to find, organize and use. All the panels are re-sizeable! And the dark skin is beautiful and very relaxing interface for long work sessions!

MAinType adapts splendidly to 25:9 screen ratio and the work is even more easy, because the columns of the font list not only can be moved, but resized to show larger, and better, and all the panels are beautifully resized. Fantastic.

As some type faces only have caps, you can test my phrases by writing one in all caps and one in upper/lower on the same screen so you can see the contrast, if any. For visual purposes, you can capture a test along with font name using a screen capture program, then compare them all before committing on the one/s that fit the best in the design.

In terms of font management, this beats what Adobe has to offer.

Other tools or companies often try to make it look like dealing with fonts is trivial, while it isn't.