What is Pseudo-Localization?

Pseudo-localization is an i18n testing technique: instead of translating strings into a real language, you transform them mechanically, swapping letters for accented equivalents, padding length, and wrapping them in markers. "Save changes" might become something like "[Šåvé çhåñgéš ~~~]". The app stays readable to your own team but behaves like a foreign-language build.

Each transformation catches a class of bug. Accented characters expose encoding and font problems. Padding simulates the expansion many languages need, in general translated text often runs longer than English, revealing truncation and broken layouts. The brackets make untranslated, hardcoded strings jump out, because anything without brackets never went through the translation layer.

The technique is cheap to automate: generate a pseudo locale from your source strings, switch the app to it, and click through key screens. Doing this before real translation starts means layout and hardcoding fixes happen once, not once per language.