About NihongoDera

Japanese dictionaries, tools, and more

What is NihongoDera?

NihongoDera started as an idea for a simple Japanese-English dictionary site with one goal: be an easy-to-use, good looking Japanese-English dictionary. But why stop there? What else could be done with all the data on a simple dictionary site? How could this data be used to benefit people who are learning/using Japanese? When I started to ask myself these questions and explore possible answers, I realized that my simple dictionary site was not at all what I wanted. Almost a full year in development, NihongoDera strives to be not only the best dictionary site out there, but also a site to help you use Japanese in whatever situation you find yourself in. Whether student or working stiff, Japanese enthusiast or computer programmer, I want to help you use Japanese better. On top of the dictionary, NihongoDera offers a growing collection of tools to fulfill this purpose. Have an idea for a new one? Drop me a line and I'll do my best to make it a reality.


The EDICT Japanese-English file is the main dictionary file used by NihongoDera. Managed by Jim Breen, the file contains about 170,000 entries and includes various kanji forms and readings, usage notes, and cross-references.

The KANJIDIC file, also managed by Jim Breen, has 6,355 kanji entries. Each entry has information about meanings, readings, stroke count, frequency, and other useful info. All kanji information on NihongoDera comes from this file.

The mysterious EJDict is a English-Japanese dictionary file that has been floating around the internet for a while. I can't find any reiable info about its origin, so if you know something, please let me know. Although it is not as complete as the EDICT file, it has definitions for most common words.

All example sentences on this site were downloaded from the Tatoeba website's download page. The site contains nearly 5 million sentences (over 180,000 in Japanese) in 297 languages. Many come with translations to other langauges and audio files.

KanjiVG is a collection of SVG files that describe the kanji. Each kanji is represented by one SVG that contains all sorts of meta data about the kanji. The SVG strokes are ordered by stroke order to ease animation.

Kanji and word Japanese Language Proficiency Test levels were adapted from lists found on this site.

English pronunciation information was extracted from the CMU Dict file, maintained by Carnegie Mellon University. The file contains 134,000 English words and their North American pronunciation. The file stores pronunciation data using ARPAbet symbols, which was converted to easier to read IPA and a spelling approximation using this tool.