Japanese Notation Variants Checker (Proofreading)
Paste Japanese text to flag likely spelling inconsistencies with a dictionary of a few hundred entries plus full-width/half-width rules, and get a recommended form for each. It is a lightweight checker without morphological analysis. To count characters, use the Character Counter; to convert widths in bulk, try the Full-width / Half-width Converter.
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Write one "before>recommended" pair per line to detect it like a dictionary entry.
Notes
- Detection is mechanical, based on a dictionary and symbol rules. Proper nouns, quotations, technical terms and house styles may be correct as written, so a person should make the final call.
- There is no morphological analysis, so context-dependent cases (such as 出来る used as a noun) and variants missing from the dictionary are not detected.
- Recommended forms are examples based on general usage and official-document conventions. If your publication has its own style guide, add its rules under custom rules.
- For full/half-width checks, the minority form is flagged when both appear in the same text. Brackets inside English text and symbols in URLs are ignored.
- Your text is processed only in your browser and is never sent to a server.
Glossary
Notation variants (表記ゆれ)
The same word written in several ways, such as different okurigana, kanji versus kana, katakana spellings, or full-width versus half-width characters. It makes a document feel inconsistent and harder to search.
Okurigana (送り仮名)
Kana written after a kanji to show its ending, such as 行う versus 行なう. Words with more than one accepted spelling are a common source of inconsistency.
Style guide (用字用語集)
A publication or company rule set that fixes which kanji, kana and words to use, for example whether to write できる or 出来る.
FAQ
What kinds of inconsistencies can it detect?
Okurigana (行なう vs 行う), kanji vs kana (出来る vs できる), katakana spellings (ソフトウエア vs ソフトウェア), terms and units (3ヶ月 vs 3か月), half-width kana, and mixed full/half-width digits, letters, brackets and punctuation. Only dictionary entries and the symbol rules are covered; other variants are not detected.
Is the recommended form always correct?
No. It is one example based on common usage and official-document conventions. Proper nouns, quotations, technical terms, and a publication or company style guide may call for another form. Long vowel marks are off by default because house styles differ.
What does "Yes (mixed)" in the recommended-form column mean?
The recommended form of the flagged text (for example 行い for 行ない) also appears elsewhere in the same text, so the writing is split between two forms. Those are the best places to unify first.
How do I write custom rules?
Write one "before>recommended" pair per line, for example お客さま>お客様. Symbols are treated as plain characters, so no regular expression is needed. If a custom rule hits the same spot as a dictionary entry, the custom rule wins.
Is my text sent anywhere?
No. Everything is processed in your browser, so it is fine for unpublished drafts and internal documents.
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