In my kanji to romaji translator I added an option that allows you to translate Japanese text to International Phonetic Alphabet (IPA) symbols.
First, I wanted to follow the Japanese IPA chart from Sanseido Dual Dictionary, but finally I decided to use the information from Wikipedia's article on Japanese phonology. By the way, there's a difference between a set of IPA symbols used in this article and the one in the IPA chart for Japanese which is also from Wikipedia. For example, I used [n] (but not [ɲ]) for the phoneme /n/ in syllables にゃ, にゅ, にょ.
At the same time I fixed some bugs that appeared when one was trying to translate Japanese text to romaji and activate devoicing of the vowels /i/ and /u/ at the same time. And the Japanese punctuation signs are now converted to their English equivalents when you choose to translate to romaji or IPA.