10ten Japanese Reader (Rikaichamp) is a Chrome add-on developed by Birchill. It is a free program in the Browsers category, specifically in the Add-ons & Tools subcategory. This add-on allows users to translate Japanese text by simply hovering over words.

The main features of 10ten Japanese Reader include pitch accent information, automatic dictionary updates, recognition of various grammatical forms and characters, translation of Japanese numbers and yen amounts, translation of Japanese-era years into Gregorian years, translation of 畳/帖 measurements into square meters, translation of shogi moves, support for a wide range of web content, and compatibility with non-English dictionaries.

Versionof 10ten Japanese Reader includes a collapsed popup window to show only the most relevant results by default, kanji details for all kanji in the longest matched word, settings for changing the font size of the popup, support for dark mode on the options page, an option to disable looking up words by tapping on them on touchscreen devices, and WaniKani level data.

Overall, 10ten Japanese Reader (Rikaichamp) is a useful Chrome add-on for anyone learning or working with the Japanese language. Its features provide convenient and quick translations, making it a valuable tool for understanding Japanese text.