N400proBuilt to help you pass — not just to memorize.
Every feature is designed around how the naturalization interview actually works.
Learn mode
Browse all 128 questions with accepted answers and clear explanations. Mark what you've mastered.
Practice quizzes
10 or 20 random questions, instant feedback, and automatic focus on the ones you got wrong.
Exam simulation
Twenty questions, pass at twelve correct — the 2025 USCIS format, including the rule that the officer stops early once the result is decided.
Three languages
Switch between English, Spanish, and German at any time. Learn in your language, answer in English.
Progress tracking
See which of the 128 questions you've mastered and where to focus next.
Categories that matter
American Government, American History, and Integrated Civics — organized the way USCIS teaches them.