A KOReader plugin that brings SKK (Simple Kana to Kanji) style Japanese input to every text field in KOReader.
Romaji Kanji → reading かんじ → kanji candidate 漢字, with the candidate bar offering homophones.
Works on all KOReader platforms:
| Platform | Input method |
|---|---|
| Kindle, Android, PocketBook (touch only) | Virtual keyboard (🌐 → 日本語 SKK) |
| SDL emulator / devices with a physical keyboard | Physical keys via SKKInputText |
Related: koreader-tategumi is a KOReader fork with Japanese vertical text (縦書き) rendering support. It can be used together with this plugin for a more complete Japanese reading and text-input setup.
- Romaji → hiragana → kanji conversion in SKK style
- Bundled dictionary (
SKK-JISYO.Lconverted to UTF-8, ~5.9 MB) — loaded instantly via SQLite - User dictionary: register new words, view usage history, delete entries, export
- Add extra dictionaries from settings (EUC-JP files auto-converted with iconv)
- Touch-friendly virtual keyboard with number row and Japanese punctuation
- Candidate cycling with wrap-around; direct selection by number keys (1–9)
- Hiragana / Katakana / ASCII mode switching
- In-app update check (Menu → SKK → Check for updates)
- Zero core KOReader file modifications — drop-in plugin
- Copy the
skk.koplugin/folder into your KOReaderplugins/directory. - Start KOReader.
- For the touch virtual keyboard, open any text field and tap the 🌐 globe key; select 日本語 SKK from the layout list.
The plugin is active as soon as it loads. Physical-keyboard typing in any input
field uses SKK conversion automatically; Ctrl+\ toggles SKK on/off per field,
and l switches to ASCII mode within SKK. On touch devices, choosing a non-SKK
layout from the 🌐 menu falls back to plain input.
First run: the bundled dictionary is converted to a SQLite database on first use. This takes a few seconds and shows a "変換中…" progress message. Subsequent starts are instant.
When the plugin is enabled, every InputDialog text field uses SKKInputText.
On the SDL emulator (Linux / macOS / Windows desktop build) the virtual keyboard
is automatically shown so you can see the current mode.
| Key | Action |
|---|---|
a–z |
Type romaji → committed as hiragana (or katakana / ASCII) |
Shift+letter |
Start kanji-conversion mode ▽ |
Space (in ▽) |
Look up candidates → ▼ mode |
Space / n (in ▼) |
Next candidate (wraps around) |
p (in ▼) |
Previous candidate |
1–9 (in ▼) |
Select candidate by number |
Enter |
Commit current composition |
Backspace |
Delete character / cancel conversion |
x (in ▼) |
Cancel candidate selection |
q |
Toggle hiragana ↔ katakana mode |
l |
Switch to ASCII pass-through mode |
Ctrl+\ |
Toggle SKK on/off for this field |
The SKK keyboard has 5 rows. The number row never changes:
- Normal mode — type
1–0directly - SELECT mode —
1–9select candidates directly;xor Backspace cancels
| Key | Normal (no modifier) | ⇧ (Shift) | ⌥ (Symbol) | ⇧+⌥ |
|---|---|---|---|---|
| Number row | 1 … 0 | ! … ) | 、 。 ー ・ 「 」 ？ ！ 〜 … | ！ … ） |
| Q row | q … p | Q … P | - _ + = / \ ' " < > | １ … ０ |
| A row | a … ; | A … : | 『 』 【 】 （ ） ［ ］ 〈 〉 | － … ． |
| Z row | z … m | Z … M | ~ ` | { } [ ] | 々 〆 〒 ※ ☆ ★ ゜ |
| Punctuation | 。 (A mode: .) | 、 (A mode: ,) | ? | ゛ |
- Tap a shifted letter (e.g. Shift + K) to enter ▽ mode.
- Type the reading in romaji.
- Tap Space — the first candidate appears as inline preedit:
▼漢字 [2:幹事 3:監事…] - Continue tapping Space to cycle, or tap a number key to select directly.
- Tap Enter to commit, or tap x (or Backspace) to cancel.
If no candidates are found, a registration dialog appears so you can add the word to your user dictionary.
The bundled SKK-JISYO.utf8 is derived from
SKK-JISYO.L (GPL-2.0+) and is automatically
kept up to date by CI (weekly sync from upstream).
Menu → Tools → SKK Japanese Input → Dictionaries → Add dictionary…
Enter the full path to a UTF-8 or EUC-JP SKK dictionary file.
EUC-JP files are auto-converted with iconv when available (Linux/macOS desktop;
not available on Kindle).
Words registered during conversion are stored in a SQLite user dictionary:
Menu → Tools → SKK Japanese Input → User dictionary
- View all registered words with usage counts and last-used date
- Delete individual entries
- Export to
.utf8format for backup or transfer
Menu → Tools → SKK Japanese Input → Check for updates
Checks GitHub for a new release and downloads all plugin files (including the updated dictionary) over WiFi. A restart prompt appears on completion.
The dictionary is also updated automatically via CI every week; users who run
"Check for updates" will always get the latest SKK-JISYO.utf8.
| Romaji | Kana | Romaji | Kana |
|---|---|---|---|
| a / i / u / e / o | あいうえお | ka ki ku ke ko | かきくけこ |
| sa si/shi su se so | さしすせそ | ta ti/chi tu/tsu te to | たちつてと |
| na ni nu ne no | なにぬねの | ha hi fu he ho | はひふへほ |
| ma mi mu me mo | まみむめも | ya yu yo | やゆよ |
| ra ri ru re ro | らりるれろ | wa wi we wo | わゐゑを |
| ga gi gu ge go | がぎぐげご | za zi/ji zu ze zo | ざじずぜぞ |
| da di du de do | だぢづでど | ba bi bu be bo | ばびぶべぼ |
| pa pi pu pe po | ぱぴぷぺぽ | nn / n+consonant | ん |
| z, / z. | 、。 | z[ / z] | 「」 |
| z- | 〜 | z/ | ・ |
Double a consonant before a vowel for sokuon: kk → っk (e.g. kka → っか).
- Plugin code: GPL-2.0-or-later
- Bundled dictionary (
SKK-JISYO.utf8): GPL-2.0-or-later (from skk-dev/dict)