Copied identifiers, spreadsheet values, search terms, or East Asian text use inconsistent character widths that another system treats differently.
Fullwidth and Halfwidth Character Converter
Convert Latin letters, numbers, spaces, punctuation, and supported Japanese kana between fullwidth and halfwidth forms locally.
Start here
Paste the text you want to normalize.
Browser-first
Your text is converted locally in your browser and is not uploaded to a server.
Useful for
Normalize IDs or numbers rejected by a form
Mode descriptionFull-width to half-width
Convert full-width letters, numbers, punctuation, and spaces to half-width.
Input characters64
Output characters64
Changed characters11
Quick answer
Convert text between fullwidth and halfwidth forms
Normalize supported Latin letters, numbers, spaces, punctuation, and Japanese kana, or convert compatible characters to fullwidth display forms.
Width conversion is not translation or case conversion and is not a complete substitute for application-specific Unicode normalization.
Text Cleaner: Clean messy text by trimming lines, removing empty lines, merging lines, or converting one item per line into a comma list.
About this tool
Convert Latin letters, numbers, spaces, punctuation, and supported Japanese kana between fullwidth and halfwidth forms locally.
Your text is converted locally in your browser and is not uploaded to a server.
Reminder
Width conversion is not a complete Unicode normalization or transliteration system. Review Japanese combining marks, unusual symbols, code, passwords, and identifiers before replacing the original text.
How to use it
- Paste the text you want to normalize.
- Choose fullwidth to halfwidth or halfwidth to fullwidth conversion.
- Review the converted text and copy it.
Common use cases
- Normalize IDs or numbers rejected by a form
- Convert fullwidth Latin text copied from East Asian documents
- Prepare consistent text for spreadsheets or imports
- Convert supported halfwidth Japanese kana to fullwidth forms
What Width Conversion Changes
Fullwidth and halfwidth are Unicode presentation forms commonly encountered in East Asian text. Width normalization can make copied identifiers, search terms, and spreadsheet values more consistent without translating their meaning.
| Input | Converted form | Example use |
|---|---|---|
| ＡＢＣ１２３ | ABC123 | Normalize a Latin identifier |
| ABC 123 | ＡＢＣ １２３ | Create fullwidth display text |
| ｶﾀｶﾅ | カタカナ | Normalize supported Japanese katakana |
Review Identifiers and Japanese Text
Characters that look similar can still have different code points. Review converted account IDs, filenames, formulas, code, URLs, and Japanese combining marks before using the result in another system.
- Width conversion is different from uppercase or lowercase conversion.
- It is not a complete replacement for application-specific Unicode normalization.
- Keep the original text until the destination accepts the converted value.
FAQ
What are fullwidth characters?
They are Unicode forms designed to occupy a square-like width in East Asian typography, such as Ａ, １, and a fullwidth space.
Can it convert Japanese kana?
It supports common halfwidth and fullwidth Japanese katakana mappings, including many voiced and semi-voiced combinations.
Is this the same as changing letter case?
No. Width conversion changes Unicode character forms; it does not generally change uppercase letters to lowercase or translate text.
Is my text uploaded?
No. Conversion runs locally in your browser.