KoguNavi

Environment-dependent / Machine-dependent Character Checker

Check Japanese text for characters that can break older forms, email systems, or submission workflows, then review suggested safer replacements.

Local in browser

Runs in your browser for this tool. Input is not uploaded.

What it helps with

  • Check text before sending Japanese email campaigns
  • Review text before pasting into Japanese forms
  • Find characters that may cause mojibake before document submission
  • Review common characters such as ①, ②, ㈱, ㈲, 髙, 﨑, Ⅰ, Ⅱ, ㍉, and ㌔

How to use

  1. Paste Japanese text before email delivery, form submission, document submission, or publishing.
  2. Review common characters such as ①, ②, ㈱, ㈲, 髙, 﨑, Ⅰ, Ⅱ, ㍉, and ㌔.
  3. Review detected positions, character types, and replacement suggestions. Suggestions still need context.
  4. Copy the suggested replacement text or apply it to the input.

Examples

Circled numbers

Input

持ち物: ①申請書 ②本人確認書類

Output

持ち物: (1)申請書 (2)本人確認書類

Company symbol

Input

㈱高橋商事

Output

(株)高橋商事

Variant kanji

Input

髙橋さんと﨑山さん

Output

高橋さんと崎山さん

Good to know

  • Detects a practical set of common characters, not every Unicode compatibility character.
  • Replacement suggestions are context-dependent and should be reviewed.
  • This tool does not guarantee that a target system will accept the text.

FAQ

Does this detect every risky Unicode character?
No. It focuses on a practical set of common Japanese compatibility and environment-dependent characters.
Are replacements always correct?
No. They are suggestions, and names, company names, or official documents may require a specific character.
Does this upload text?
No. Character checking runs in your browser and input is not sent to a server.

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