We propose an interactive system for translating Japanese into Braille on the Web. Accurate automatic translation is difficult due to the ambiguous, complicated translation rules. Braille expressions must be made consistent throughout a text, even if a translation can be interpreted in more than one way. Braille translation productivity is slowed by the need for user intervention. Our system provides interactive Japanese-to-Braille translation and updates the knowledge base to keep results consistent and improve translation accuracy. Experimentals show that case acquisition reduces errors and that the user interface reduces output instability without requiring that the whole document be rechecked.