Fullwidth Low Line Letter
The fullwidth low line _ (U+FF3F) is a fullwidth underscore-like character used for layout and text styling.
U+FF3F
The fullwidth low line (_) looks like an underscore but is designed to occupy fullwidth space. It’s commonly used when you need consistent character width, especially in East Asian typography. You can copy it directly or use the provided code escapes in your HTML, CSS, and JavaScript.
Fullwidth Low Line Letter Meaning
The symbol _ is the FULLWIDTH LOW LINE (Unicode U+FF3F). Visually, it resembles a typical underscore but differs in width: it’s a fullwidth character intended to align better with fullwidth text. In practice, people use it as a typographic alternative to “_” when designing text that must keep spacing consistent across languages, or when matching fullwidth style conventions. It can also be used as a decorative underline placeholder in headings, profile labels, or form-like displays where a fullwidth character fits the surrounding font metrics more naturally than the ASCII underscore.
Common uses
- •Building consistent-looking “underline” or separator lines in fullwidth text layouts
- •Creating simple placeholders in headings or UI labels where spacing must stay uniform
- •Designing social media text blocks that align across devices and fonts
- •Replacing ASCII underscores in environments that prefer fullwidth characters
- •Formatting usernames, tags, or identifiers for visual style consistency
Examples
_ Fullwidth Low Line (U+FF3F)
- _User_ID
- _Section_01
- _お問い合わせ_contact
- _タグ_label
- _フォロー_more
Variations
Technical codes
| Unicode | U+FF3F | |
| HTML Entity | _ | |
| HTML Code | _ | |
| CSS | \FF3F |
FAQ
What does the Fullwidth Low Line letter mean?
The symbol _ is the FULLWIDTH LOW LINE (Unicode U+FF3F). Visually, it resembles a typical underscore but differs in width: it’s a fullwidth character intended to align better with fullwidth text. In practice, people use it as a typographic alternative to “_” when designing text that must keep spacing consistent across languages, or when matching fullwidth style conventions. It can also be used as a decorative underline placeholder in headings, profile labels, or form-like displays where a fullwidth character fits the surrounding font metrics more naturally than the ASCII underscore.
Is _ the same as the normal underscore _?
No. _ is the FULLWIDTH LOW LINE (U+FF3F), which occupies fullwidth spacing, while _ is typically the ASCII underscore character. They can look similar, but spacing and alignment may differ.
How do I paste _ into HTML?
You can paste the character directly, or use the HTML entity: _.
What CSS escape can I use for this character?
Use the CSS escape form: \\FF3F.
What JavaScript escape works for _?
Use: \\u{FF3F}.