A type of machine translation that translates text using predefined linguistic rules and dictionaries.
Rule-Based Machine Translation (RBMT) systems analyze the grammar, syntax, and semantics of the source language, map this information into an intermediate representation, and then generate text in the target language according to its grammatical rules.
Unlike statistical or neural approaches, RBMT relies on human-crafted rules rather than large volumes of bilingual training data. This makes it highly controlled and predictable but often less natural in fluency.
Its rule-driven nature means it can enforce consistency across large projects and make quality checks easier for teams.
In localization, RBMT is useful when accuracy and consistency are more important than style. It works well for technical content, and documents that rely on strict terminology.
Unlike newer MT methods, RBMT gives linguists more direct control over terminology and structure, which can be critical when precision outweighs fluency. This makes it a niche but dependable choice for industries where accuracy is non-negotiable.
RBMT was the first widely used commercial machine translation technology and remains relevant in specialized fields where precision, terminology control, and linguistic transparency are essential. Even if newer approaches are more common today, RBMT still helps teams deliver reliable translations in projects where precision matters.