Full width and half width
Ａ１２３ ⇄ A123, ﾊﾞｯｸｱｯﾌﾟ ⇄ バックアップ.
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Output
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Example
Example: a customer row with full-width digits and half-width katakana, in two passes
A row exported from a Japanese shop system reads ﾔﾏﾀﾞ ﾊﾅｺ,０９０－１２３４－５６７８,ｈａｎａｋｏ＠ｅｘａｍｐｌｅ．ｊｐ. The new system wants half-width digits and letters but full-width katakana: two directions in one line, so it takes two passes.
- Pass 1: To half width, with only “Letters, digits and punctuation” ticked. The phone number becomes 090-1234-5678 and the address hanako@example.jp; the katakana is left alone.
- Pass 2: paste that result back, choose To full width and tick only Katakana. ﾔﾏﾀﾞ ﾊﾅｺ becomes ヤマダ ハナコ; with Spaces off, the space between the names stays an ordinary one.
- The counter goes from 40 characters to 39: half-width ﾀﾞ is two characters, ﾀ and a voiced mark, while full-width ダ is one.
| Typed | Setting | Result |
|---|---|---|
| ＴＡＮＡＫＡ Ｔａｒｏ | To half width, all ticked | TANAKA Taro |
| 〒１５０－００４１ | To half width, all ticked | 〒150-0041 |
| ﾊﾞｯｸｱｯﾌﾟ | To full width, all ticked | バックアップ |
| ヤマダ ハナコ | To half width, all ticked | ﾔﾏﾀﾞ ﾊﾅｺ |
| ﾔﾏﾀﾞ ﾊﾅｺ | To full width, all ticked | ヤマダ ハナコ |
ヤマダ ハナコ,090-1234-5678,hanako@example.jp: digits and address in the half width the system checks, the name in full-width katakana, nothing else in the row touched.
How it works
- Paste the text. The result updates as you type.
- Choose the direction: to half width for a form that rejects full-width digits, to full width for a system that expects them.
- Switch off the kinds of character you want left alone — converting the letters but not the katakana, for instance.
- Copy the result.
Frequently asked questions
- What is the difference between the two widths?
- Japanese typesetting has two forms of the same characters: full width, which takes the square of a Japanese character (ＡＢＣ１２３), and half width, which is the ordinary Latin form (ABC123). Katakana exists in both too. Which one a system wants is arbitrary and rarely explained, which is why this conversion is an everyday chore in Japan.
- Does it handle voiced katakana properly?
- Yes, and this is where simple conversions go wrong. Half-width katakana writes バ as two characters — ﾊ followed by a voiced mark — while full width writes it as one. Going to full width joins them; going to half width splits them again. ﾊﾟ and the small forms are handled the same way.
- Why is there a separate option for spaces?
- Because the ideographic space (U+3000) is a character in its own right and is a character wide. A form that rejects it will not tell you why. Keeping it on turns it into an ordinary space going one way, and back going the other.
- What is left alone?
- Hiragana, kanji and anything outside the ranges being converted. Only the characters that genuinely have two widths are touched.
- How do I turn full-width numbers into normal ones?
- Choose To half width and leave only “Letters, digits and punctuation” ticked: ０９０－１２３４－５６７８ becomes 090-1234-5678, and the full-width letters, @ and dots of an e-mail address are converted with them. Katakana stays as it is unless Katakana is ticked too.
- Why does the character count change?
- Because half-width katakana writes a voiced sound as two characters. ﾊﾞｯｸｱｯﾌﾟ is eight characters and バックアップ six, so going to full width shortens the text and going back lengthens it. Letters and digits keep their count both ways: ＴＡＮＡＫＡ is five characters, and so is TANAKA.
- Is my text uploaded?
- No. It is converted in this page as you type. Names, addresses and customer records are exactly what these conversions are for, and none of it leaves the device.
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