Overview
Keigo • Natural Japanese • Proofread • Furigana • Read aloud. Works from English & Chinese.
Your Japanese writing assistant on every website: select text, choose a style, and replace it in place. • Keigo — turn casual Japanese into business-ready keigo • Proofread — fix grammar and particles, with every edit highlighted • Gmail — a Proofread button right next to Send • English or Chinese in, natural Japanese out • Furigana and read-aloud to check readings and pronunciation No copying, pasting or switching tabs — Tadashii Kotoba (正しい言葉) works wherever you write. HOW IT WORKS 1. Select text on any page. 2. Choose Keigo, Standard or Proofread from the toolbar (or right-click → Tadashii Kotoba). 3. In editable fields, click Replace to put the result in place; anywhere else, copy it. FEATURES • Keigo — Rewrites casual Japanese into polite, business-appropriate keigo. • Standard — Produces clear, natural Japanese for everyday writing. • Proofread — Corrects grammar, particles, conjugation and wording, and highlights every change so you can see exactly what was edited. • Replace in place — When the selected text is in an editable field (a text box, an editor, an email body), a Replace button appears on the result card and swaps in the new text with one click. On read-only pages, copy the result instead. • English and Chinese input — Draft in English or Chinese and convert it directly into natural Japanese. • Furigana — Shows readings above every kanji in the result. • Listen — Reads the Japanese aloud in a natural, high-quality voice and highlights each phrase as it plays. • Gmail — When your draft is in Japanese, a Proofread button appears next to Send. Review the highlighted edits before applying them. If you prefer instant replacement, every change can still be reviewed or undone. • Right-click menu — Every action is also available from the context menu, including in PDFs. The selection toolbar can be turned off in Settings. For local files, turn on “Allow access to file URLs” on the extension’s details page. • Interface in English, Japanese and Traditional Chinese. PLANS Start without an account. Sign in for free at tadashii-kotoba.com for a larger daily allowance, or upgrade to Pro for the largest monthly allowance. Your allowance is shared with the website, and your current plan is shown in the toolbar. DESIGNED FOR • Professionals writing to Japanese clients and colleagues • Japanese learners who want to check readings and pronunciation as they write • Anyone who drafts in English or Chinese and needs to send natural Japanese PRIVACY Text is sent to our servers only when you run an action (rewrite, proofread, furigana or read aloud), and only to provide that feature. We never sell your text. Privacy policy: https://tadashii-kotoba.com/privacy Website: https://tadashii-kotoba.com Support: support@isshin.tech
Details
- Version1.0.8
- UpdatedOctober 12, 2026
- FeaturesOffers in-app purchases
- Size120KiB
- Languages3 languages
- Developer
- TraderThis developer has identified itself as a trader per the definition from the European Union and committed to only offer products or services that comply with EU laws.
- D-U-N-S773249824
Privacy
Tadashii Kotoba – Natural Japanese & Keigo has disclosed the following information regarding the collection and usage of your data. More detailed information can be found in the developer's privacy policy.
Tadashii Kotoba – Natural Japanese & Keigo handles the following:
This developer declares that your data is
- Not being sold to third parties, outside of the approved use cases
- Not being used or transferred for purposes that are unrelated to the item's core functionality
- Not being used or transferred to determine creditworthiness or for lending purposes
Support
For help with questions, suggestions, or problems, visit the developer's support site
