Full-width & half-width converter

How to use

1. Choose the direction: full-width to half-width, or the reverse.
2. Switch on only the classes you want converted: alphanumerics, symbols, katakana, or spaces.
3. Optionally convert between hiragana and katakana; that step runs after the width conversion.
4. Paste text into the left pane and copy the result from the right.

Notes

• •Voiced half-width katakana are two characters; widening them composes one, which changes the length.
• •Narrowing does the opposite and makes the text longer—check the result against any length limit.
• •Kanji and hiragana have no width variants, so they pass through untouched.
• •The ideographic space (U+3000) is only converted while the Space class is switched on.