Internationalizing & Localizing Your Modern JavaScript App The current state of internationalization and localization (sometimes called i18n and l10n) tools for modern javascript apps is discussed, both for client-side and server-side rendered applications, including how to manage translation strings, handling plural forms, testing, translation process, and interfacing with external translation providers. I'll go over the currently available libraries, status of the INTL browser standard, and what I've found successful. The goal is to achieve an easy and well-translated app that scales to your audience, no matter where they are located and what language they speak.