Full-width & Half-width Converter
Convert between full-width and half-width characters.
⌷Full-width & Half-width Converter
All processing happens locallyWhat this tool does
Full-width & Half-width Converter is a character width converter, processing happens locally in your browser with no upload.
Many forms accept only half-width digits, yet text copied from documents often carries full-width characters, causing validation errors. One conversion fixes it.
How to use it
- Paste or type your content into the input field at the top, or press the sample button to load demo data.
- Adjust the options below the input, such as output format, separators, letter case or precision.
- Press the main button to run the conversion. Results appear instantly in the output panel without a page reload.
- When the result looks right, use the copy button in the corner, or download it as a local file.
Tips and notes
Clean up stray spaces and line breaks before pasting for more accurate results.
FAQ
Yes, the full-width space becomes a normal space, a hidden cause of many validation failures.
No. Only letters, digits, punctuation and spaces have width variants.
Yes. The tool is completely free with no usage limits, and you never need an account or a sign-in.
No. All processing runs locally in your browser, so the input never reaches a server and is never logged or stored.
Yes. The layout is mobile-first, so inputs and buttons stay comfortable on phones and tablets in both orientations.
Yes. A copy button in the output panel puts the result on your clipboard, and you can also download it as a text file.