Radical is a free kanji dictionary application for iOS and Android, developed by Carlos Ramos Fuentes, a Japanese language teacher. Its core differentiator is an explicit treatment of phonetic radicals (形声文字, keiseimoji), showing learners both the meaning-indicating and pronunciation-indicating components of each phono-semantic compound kanji.
In-Depth Explanation
Platform: iOS (App Store ID 6760137001, title: Radical: Kanji Dictionary) and Android (Google Play: com.kanji.radical, title: Radical.). The app name differs slightly between platforms. The dictionary contains 6,368 kanji entries, 210,641 word entries, 246,737 example sentences, and 9,756 JLPT-tagged entries.
The majority of kanji used in Japanese (roughly 80% by some linguistic analyses) are phono-semantic compounds — characters combining a semantic radical that provides a general meaning hint with a phonetic radical that historically indicated the character’s pronunciation. Most kanji learning approaches teach only the meaning radical. The Radical app aims to make both components of each kanji visible and explicit, with the goal that learners can use the phonetic component to infer or recall the on’yomi reading rather than memorizing it in isolation.
For example, a group of characters sharing the same phonetic component may all share a similar or identical on’yomi reading — a pattern that, once recognized, can reduce the memorization burden for learners.
Each kanji entry in the app identifies:
- The meaning-indicating radical
- The phonetic radical (where the character is a phono-semantic compound)
- The on’yomi reading(s) and kun’yomi reading(s)
- Known reading exceptions where the phonetic prediction does not hold
The dictionary supports search in English, Japanese (kanji/kana), and romaji. The JLPT tagging covers N5 through N1.
The app was developed independently by a Japanese language teacher. As of early 2026, it was a brand-new release with no accumulated public ratings in the App Store.
Common Misconceptions
“All kanji follow the phonetic radical pattern.”
Phono-semantic compounds represent a large proportion of the kanji set, but not all. Some kanji are pictographic (象形, shōkei), ideographic (指事, shiji), or semantic compounds (会意, kaii) without a phonetic component. The app accounts for reading exceptions within the phono-semantic category as well.
Social Media Sentiment
No substantial community discussion of the Radical app was observed as of early 2026. The app was newly released at the time of writing and had not yet accumulated reviews in the App Store. The concept of phonetic radicals as a kanji learning strategy does appear independently in Japanese-learning communities — particularly among intermediate learners seeking systematic approaches to on’yomi readings — but community discussion of this specific application was not yet present in meaningful quantity.
Last updated: 2026-05
Related Terms
See Also
Research
- Ramos Fuentes, C. (n.d.). Radical: Kanji Dictionary [Mobile application, iOS]. App Store (ID 6760137001). https://apps.apple.com/app/id6760137001
Summary: Primary source for iOS-specific details including App Store ID, feature set (6,368 kanji, 210,641 words, 246,737 example sentences, 9,756 JLPT tags, phonetic radical instruction, courses), and data sources (JMDict, KANJIDIC, Tatoeba, Ishizawa-sensei’s phonetic radical research). Verified May 2026.
- Ramos Fuentes, C. (n.d.). Radical. [Mobile application, Android]. Google Play (com.kanji.radical). https://play.google.com/store/apps/details?id=com.kanji.radical
Summary: Source confirming Android availability (1,000+ downloads, updated April 2026). App is listed under a slightly different title (“Radical.”) on Google Play versus “Radical: Kanji Dictionary” on the App Store. Feature set and developer are the same across platforms. Verified May 2026.
- Henshall, K. G. (1988). A Guide to Remembering Japanese Characters. Charles E. Tuttle.
Summary: Provides etymological and structural analysis of kanji including phono-semantic compounds; supports the pedagogical value of teaching phonetic radicals explicitly to help learners infer on’yomi readings — the core approach of the Radical app.
- Seeley, C. (1991). A History of Writing in Japan. E. J. Brill.
Summary: Documents the historical development of the Japanese writing system and the structure of kanji, confirming that phono-semantic compounds represent the majority of Chinese-origin characters — the foundational premise behind the Radical app’s phonetic-radical-first teaching method.