Text Style Checker

Detect fullwidth alphanumeric characters, fullwidth spaces, and halfwidth katakana on any webpage.

Catch text style inconsistencies, automatically. A Chrome extension that detects fullwidth/halfwidth character inconsistencies in CJK text on any webpage. Catch the issues that are easy to miss by eye. Perfect for: • Pre-publish QA on CJK (Japanese, Chinese, Korean) content • Verifying translated Japanese text uses consistent character forms • Ensuring product descriptions maintain uniform text style • Batch-checking pages before release for style violations Detection Rules: • Fullwidth Alphanumeric — Finds fullwidth letters and digits (e.g. Ａ–Ｚ, ０–９) that should typically be halfwidth • Fullwidth Spaces — Spots fullwidth spaces hidden in text, preventing inconsistent spacing • Halfwidth Katakana — Identifies halfwidth katakana (e.g. ｱｲｳ) that should typically be fullwidth Key Features: • One-click scan of the current page • Each issue shown with surrounding context for easy identification • Per-rule summary with detection counts • Works on any webpage — CMS, e-commerce, documentation, etc. Privacy: • No data is ever sent to external servers • All processing happens entirely in your browser • No personal information or cookies are collected