Yesterday I wrote about how to translate WordPress themes and plugins with Loco Translate and I mentioned also another method, which is by using Poedit.
Poedit is an open source (MIT license) program available for OS X, Windows and Linux. You can download it here.
It does not only work with WordPress, but with anything that uses the gettext package to manage translations.
In this tutorial though, you will learn how to use it to translate your WordPress theme/plugin.