Full-width / Half-width Converter

Convert Katakana between full-width and half-width forms.

The Full-width / Half-width Converter is a web-based service designed to easily convert Katakana between full-width (全角) and half-width (半角) forms, which are still commonly mixed in Japanese text environments. While the difference may appear to be merely a matter of character width, it actually stems from distinctions in Unicode character encoding, which can lead to search errors, data inconsistencies, and system input limitations. In contexts such as Japanese e-commerce product registration, global online retail operations, translation and localization, or data cleaning processes, the mixing of full-width and half-width characters can cause unexpected technical issues.

This service instantly converts entered Katakana words or sentences into the desired full-width or half-width format. It accurately processes voiced sounds (e.g., ガ / ｶﾞ), semi-voiced sounds (e.g., パ / ﾊﾟ), as well as small characters (e.g., ャュョ / ｬｭｮ). No installation is required, and users can obtain results with a single click. If corrections are needed or a fresh start is preferred, the CLEAR button allows all input content to be reset easily.

More than just a simple text conversion tool, the Full-width / Half-width Converter serves as a practical utility for text normalization and data quality improvement. In environments where even a single character difference can affect search results or trigger system errors, this service provides a reliable and precise solution for users who value accuracy and detail.

Enter the alphabet letters, numbers, or Katakana text you would like to convert into the prepared rectangular input field. While some special characters are supported, the number of special characters that can be mutually converted is limited, so entering other unsupported characters is unnecessary. Once you have finished entering your text, click the appropriate conversion button located below according to your purpose. snskeyboard will then redirect you to a separate page where the result is generated. After reviewing the result, if you are satisfied with it, simply click or tap on the result area. It will be automatically copied to your clipboard!