'RomajiDesu is a free online Romaji/Japanese ⇆ English dictionary which contains the following useful tools for Japanese learners:
Japanese-Romaji-English dictionary: This is the unique English-Japanese dictionary where you just need to type your word into a single input. Your input may be Japanese (that is Kanji Hiragana, or Katakana), Romaji or English. The dictionary will find the appropriate definition and example sentences containing the word for you.
English Japanese Kanji dictionary: Include a powerful Kanji lookup form and a easy to use a multiple Kanji radicals (parts) lookup method with beautiful stroke order diagrams and detail information.
Romaji to Hiragana converter and Romaji to Katakana converter: It's useful if you know the Romaji form of some Japanese words and want to see how to write it in Hiragana/Katakana. It can also translate the word or phrases to English using Google translate engine.
Japanese to Romaji converter (beta): Help you read and lookup the meaning of a Japanese paragraph for you.