FontBase is a freeware fonts manager geared for designers or anyone with an extensive collection of fonts.

FontBase has a very simple to use user interface. Drag and drop a folder or import your fonts manually. By using folders, you can arrange your fonts for your application needs. The neat thing about that is you could have folders named for specific projects or apps. Adding fonts can load all your default Windows fonts to get started.

Features:

Use any font from Google's library in a single click as if it were local.
Play around in Preview tab, applying styling to H1, H2, and other page elements.
See all font styles on a single page, discover combinations and weights.
Activate any fonts, without the need to install! A new way to work with fonts.
Create and manage collections and explore the default ones. Activate them in a single click.
FontBase just displays your file structure as-is. No need to re-arrange or get used to it.
Good performance displaying and loading fonts.
Automatic updates included.

Having dozens, or even hundreds, of fonts, can be confusing, but FontBase is a true time saver if you need to get yours organized.