Subscript One (₁) is the Unicode character at U+2081 in the Subscripts and Superscripts block. It looks like a small lowered 1 and is common in math and science text such as x₁.
Remember
Character ₁
Unicode U+2081
Hex entity ₁
Decimal ₁
CSS escape \2081
Named entity (none)
All of these produce the same glyph: ₁. Prefer the Unicode character (or its entities) when you need that exact glyph; use <sub>1</sub> when you want semantic subscript formatting instead.
Reference
Quick Reference
One table for every form you will actually use.
Form
Code
Where it goes
Direct character
₁
HTML text (UTF-8)
Hex entity
₁
HTML markup
Decimal entity
₁
HTML markup
CSS escape
\2081
Stylesheet content
Named entity
—
Not defined in HTML5
Semantic tag
<sub>1</sub>
HTML (formatting, not the ₁ glyph)
When to use which
Situation
Use
Need the Unicode glyph ₁
Type ₁, or ₁ / ₁
Generated text via ::before / ::after
content: "\2081"
Semantic subscript for any text
<sub>1</sub>
Plain digit one (not subscript)
Type 1 (U+0031)
Looking for &sub1; or similar
Does not exist — use numeric form
See it
Live Preview
Subscript One rendered in common writing contexts.
Inline textFirst term: x₁ = 1
Large glyph₁
In an expressiona₀ + a₁ + … + aₙ
Monospacex₁ → first element
With entitiesHex: ₁ | Decimal: ₁
Semantic <sub>x1 (tag styles digit 1)
Code
Complete HTML Example
One page that shows Subscript One with the hex entity, decimal entity, CSS escape, and the semantic <sub> option. Use View Output or open the live editor.
Hex + Decimal + CSS + <sub>
Four ways to show a lowered one in a single document.
html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Subscript One (₁) in HTML</title>
<style>
#point::after {
content: "\2081";
}
</style>
</head>
<body>
<p>Subscript One using Hex Code: ₁</p>
<p>Subscript One using HTML Code: ₁</p>
<p id="point">Subscript One using CSS Entity: </p>
<p>Semantic alternative: x<sub>1</sub></p>
</body>
</html>
Subscript One using Hex Code: ₁
Subscript One using HTML Code: ₁
Subscript One using CSS Entity: ₁
Semantic alternative: x₁
How It Works
1. Hex:U+2081 → ₁ in HTML. The browser turns it into ₁.
2. Decimal: same code point as 8321 → ₁. Same result as hex.
3. CSS: use \2081 in content (not an HTML entity). #point::after appends that ₁ after the paragraph text.
4. Semantic <sub>:x<sub>1</sub> styles digit one as a subscript. Prefer this when you need meaning, not a specific Unicode glyph.
Pitfalls & Tips
Common mistakes when working with Subscript One entities.
Named?
No named entity
HTML5 does not define &sub1; or similar. Use numeric forms.
CSS vs HTML
Do not mix escapes
\2081 belongs in CSS. ₁ / ₁ belong in HTML.
₁ vs 1
Different characters
₁ is U+2081; digit 1 is U+0031. Do not treat them as the same.
Glyph vs tag
Choose intentionally
Use the Unicode glyph for exact look; use <sub> for semantic subscript on any text.
Semicolon
End references
Always finish with ; — write ₁, not ₁.
Fonts
Check the glyph
Some fonts draw ₁ weakly. If appearance matters, test the font or prefer <sub>.
Compatibility
Browser Support
Subscript One (U+2081) and its numeric entity forms (₁, ₁, CSS \\2081) are supported in all mainstream browsers. Glyph shape depends on the font.
✓ Universal support
Subscript One (₁)
Encode with hex, decimal, or CSS escape — or use <sub> for semantic formatting.
100%Browser coverage
Google ChromeSupported
Yes
Microsoft EdgeSupported
Yes
Mozilla FirefoxSupported
Yes
Apple SafariSupported
Yes
OperaSupported
Yes
Internet ExplorerAll versions
Yes
U+2081 / entitiesFull support
Bottom line: Use ₁ or ₁ for the Unicode glyph, \\2081 only inside CSS content, and <sub>1</sub> when you want semantic subscript.
Remember
Key Takeaways
Unicode: Subscript One is U+2081 (decimal 8321).
HTML: use ₁ or ₁ when you need an entity.
CSS: use \2081 inside content for generated text.
Alternative: use <sub>1</sub> for semantic subscript formatting.
One line:U+2081 → ₁ / ₁ / CSS \2081, or semantic <sub>1</sub>.
Frequently Asked Questions
Use ₁ (hex), ₁ (decimal), or the CSS escape \2081 in the content property. All render ₁. You can also paste the character ₁ directly when your file is UTF-8.
U+2081 (hex 2081, decimal 8321). It belongs to the Subscripts and Superscripts Unicode block.
No. HTML5 does not define a named entity for ₁. Use numeric references like ₁ or ₁.
Use ₁ (or its entities) when you need the exact Unicode subscript glyph. Use <sub>1</sub> when you want semantic subscript formatting for arbitrary text.
No. Digit one is U+0031. Subscript One is U+2081 — a different character with a different code point.
HTML entities (₁ or ₁) go in markup. The CSS escape \2081 is used in stylesheets (usually in the content property of ::before/::after). Both render ₁.
🤔
Did you know?
Subscript one is Unicode U+2081 (decimal 8321). HTML5 has no named entity for it — use ₁ or ₁. It is a different character from digit one (U+0031).
