To use web fonts with wide browser support, we need the font files in .woff and .woff2 format. Who does not care about Internet Explorer, Safari on Mac OS before Sierra, and a few mobile browsers can choose only .woff2 (there are tables with the browser support of the two formats on Can I use).
In this post, I show how to use the command line tool Glyphhanger to convert .ttf files to .woff and .woff2 and subset fonts to remove unused characters.