A Japanese IME converts keystrokes into phonetic (kana) and ideographic (kanji) characters and words. As keystrokes are entered, the IME attempts to guess which character or characters the keystrokes should be converted into.

Because many Japanese words have identical pronunciation, the Japanese IME's first suggestion may not be what the sentence requires. For this reason, the IME can provide a list of homophones for the user to choose from. In some cases, the homophone that the user selects becomes the IME's first suggestion the next time around.

Japanese language versions of Microsoft Windows95, Windows98, and Windows NT4.0 include the full-featured Microsoft IME (MSIME). MSIME, however, was designed to run on Japanese language versions of Windows. The Microsoft Global IME for Japanese is an ActiveX-based IME that enables the input of Japanese characters in supporting applications (such as Internet Explorer and Outlook Express) on other language versions of Windows.