Half-Width to Full-Width Converter
Convert between half-width (hankaku) and full-width (zenkaku) characters instantly. Essential for Japanese form input, data processing, and text formatting.
Common Conversion Examples
See how half-width characters map to their full-width equivalents
Understanding Zenkaku and Hankaku
Full-Width / Zenkaku (全角)
Full-width characters occupy the same width as a Japanese kanji or kana character. They are the default character format in Japanese computing. Numbers, letters, and symbols all have full-width variants that align neatly with Japanese text.
Half-Width / Hankaku (半角)
Half-width characters are the standard ASCII characters used in Western computing. They occupy half the width of a full-width character. While common in English text, they are often rejected by Japanese form validation systems.
Why This Matters
When filling out Japanese online forms, bank transfers, government applications, or e-commerce checkouts, you may encounter errors if you enter half-width numbers or letters where full-width is required. Common fields that require full-width input include phone numbers, postal codes, addresses, and account numbers. This converter helps you quickly format your text to meet these requirements.
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Explore JLPT CoursesFrequently Asked Questions
What is the difference between zenkaku (full-width) and hankaku (half-width)?
Zenkaku (full-width) characters occupy a full character cell in Japanese text, while hankaku (half-width) characters occupy half that space. Full-width is the standard in Japanese computing and is required by many Japanese websites and forms.
Why do Japanese forms require full-width characters?
Many Japanese websites, government forms, and banking systems require full-width (zenkaku) input for phone numbers, postal codes, and addresses. This stems from legacy Japanese computing standards that ensured consistent text spacing and alignment.
What characters can be converted?
All ASCII characters (letters, digits, punctuation, symbols), spaces, and half-width katakana can be converted. Hiragana, kanji, and other characters that only exist in one width remain unchanged.
How do I type full-width numbers on my keyboard?
Use your Japanese IME to switch between half-width and full-width modes. On Windows press Alt+`, on Mac use the Input Sources menu. Or simply type half-width and use this tool to convert.
Are full-width and half-width treated the same in databases?
No. Most databases and form validators treat them as different characters. This is why converting to the correct width is critical when filling out Japanese forms or querying Japanese databases.