Full-width / Half-width Converter
Convert alphanumerics, symbols, and katakana between full-width and half-width in your browser.
abc
Letters (English)
123
Numbers
alternate_email
Symbols
ア
Katakana
0 characters
transform
Conversion runs automatically as you type.
Did you know?
Half-width katakana was originally created to save memory on early computer systems. Today, it is mostly used as a stylistic choice.
ｱｲｳｴｵ
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アイウエオ
live_help Frequently Asked Questions (FAQ)
Is my data sent anywhere? expand_more
No. All conversion runs locally in your browser. Your input text is never sent to any server.
Are any characters unsupported? expand_more
It supports basic letters, numbers, symbols, and katakana. It does not convert environment-dependent characters, emoji, or kanji.
What happens to voiced sound marks in half-width katakana? expand_more
When converting to full-width, the base character and dakuten/handakuten are combined into one character (e.g., ｶﾞ -> ガ). When converting to half-width, they are split into two characters.
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