Here's what we know:
* English: This is his primary language, as he is a citizen of Gotham City, USA.
* French: Bruce Wayne's parents were French, so it's highly likely he learned French at some point. This is supported by him speaking it in some comics and animated series.
* Spanish: He has traveled to South America and interacted with Spanish-speaking characters, suggesting he knows at least basic Spanish.
* Japanese: Batman has had numerous interactions with Japanese characters like Ra's al Ghul and the Bat-family member, Cassandra Cain. He would likely have learned at least some conversational Japanese for these interactions.
* Other Languages: It's plausible that Batman knows the basics of other languages like Mandarin, Arabic, or Russian, given his global travels and contacts with various criminal organizations.
Ultimately, while there's no definitive list, Batman likely speaks multiple languages fluently and possesses a working knowledge of many others. This is part of what makes him such a formidable detective and crime fighter.