Japanese AI Humanizer — Built by a Kyoto Developer Who Speaks Japanese

Most AI humanizers translate English assumptions onto Japanese text. Suikou is built from the morphology up — 助詞, 活用形, 漢字含有率 — by someone who actually writes in Japanese.

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Why Japanese needs a different humanizer

"AI-sounding Japanese" has tells every reader recognizes: monotone sentence endings (〜です。〜ます。 on repeat), over-explicit subjects (natural Japanese omits them), English-calque punctuation (colon-led lists like 「以下のとおりです:」, full-width dashes), set cliché phrases (「〜が浮き彫りになっている」, 「今後の展開が注目される」), and an unnaturally consistent 漢字 ratio. English-trained humanizers are blind to these — so they don't fix them. Suikou removes this "AIっぽさ" from a Japanese-native angle: it varies 句末 between である / だ / です-ます, drops redundant subjects, rewrites calque punctuation and clichés into natural phrasing, and tunes the 漢字 ratio (38-45% for academic register, lower for casual) and 助詞 placement against a corpus of human-authored Japanese.

Before & after — real Japanese examples

Academic (修士論文)

Before

本研究では、深層学習モデルを用いて自然言語処理タスクを実行することにより、従来の手法と比較して優れた結果を得ることができた。

After

本研究では深層学習モデルを自然言語処理タスクに適用し、従来手法を上回る結果を得た。

Business email

Before

お忙しいところ恐縮ではございますが、お時間がございましたら、ご返信いただけますと幸いに存じます。

After

お忙しいところ恐縮ですが、ご都合のつくときにご返信いただけると助かります。

Casual (note 記事)

Before

私はこの問題について考えた結果、以下のような結論に至ったのである。

After

この問題、いろいろ考えた末にこんな結論になった。

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Thesis humanizer·Read our blog·Open full humanizer

Suikou AI is built for academic refinement and writing clarity. Users are responsible for complying with their institution's academic integrity policies.