HTML Entity for Infinity (∞)
What You'll Learn
How to display the Infinity symbol (∞) in HTML using hexadecimal, decimal, named entity, and CSS escape methods. Use it for unbounded quantities—limits (as x → ∞), infinite series, set theory, and calculus.
This character is U+221E (INFINITY) in the Mathematical Operators block (U+2200–U+22FF). Render it with ∞, ∞, ∞, or CSS \221E.
⚡ Quick Reference — Infinity
U+221EMathematical Operators block
∞Hexadecimal reference
∞Decimal reference
∞Most readable option
Name Value
──────────── ──────────
Unicode U+221E
Hex code ∞
HTML code ∞
Named entity ∞
CSS code \221E
Meaning Infinity / unbounded quantity
CSS note \221E or \0221E in content propertyComplete HTML Example
This example demonstrates the Infinity symbol (∞) using hexadecimal code, decimal HTML code, the named entity, and a CSS content escape:
<!DOCTYPE html>
<html>
<head>
<style>
#point:after{
content: "\221E";
}
</style>
</head>
<body>
<p>Infinity using Hexadecimal: ∞</p>
<p>Infinity using Decimal: ∞</p>
<p>Infinity using Named Entity: ∞</p>
<p id="point">Infinity using CSS Entity: </p>
</body>
</html>🌐 Browser Support
The Infinity symbol (∞) is universally supported in all modern browsers:
👀 Live Preview
See the Infinity symbol rendered live in different contexts:
🧠 How It Works
Hexadecimal Code
∞ uses the Unicode hexadecimal value 221E to display the Infinity symbol. The x prefix indicates hexadecimal format.
Decimal HTML Code
∞ uses the decimal Unicode value 8734 to display the same character. This is one of the most commonly used methods.
CSS Entity
\221E is used in CSS stylesheets, particularly in the content property of pseudo-elements like ::before and ::after.
Named Entity
∞ is the named entity for ∞—easy to remember and clear in source HTML.
Same visual result
All four methods produce the glyph: ∞. Unicode U+221E is in Mathematical Operators. Next: Information Source.
Use Cases
The Infinity symbol (∞) commonly appears in the following scenarios:
Limits at infinity (limx→∞), improper integrals, and infinite series.
Infinite sets, cardinality (e.g. |ℕ| = ∞), and countability.
Unbounded domains, asymptotic behavior, and infinite systems in formulas.
Document floating-point Infinity (e.g. JavaScript) in API docs and tutorials.
Calculus, analysis, and philosophy-of-math course materials.
Papers on unbounded growth, limits, or infinite processes.
💡 Best Practices
Do
- Prefer
∞for readable source markup - Keep one method (named, hex, or decimal) consistent per document
- Use semantic HTML and
aria-labelfor standalone math symbols when needed - Provide context (e.g. “as x → ∞” or “infinite set”) in mixed content
- Test rendering across browsers and fonts
Don’t
- Put CSS escape
\221Ein HTML text nodes - Confuse ∞ (infinity) with ♯ (music sharp) or other similar-looking glyphs
- Mix entity styles randomly in one file
- Assume every font renders U+221E clearly
- Skip UTF-8 (
<meta charset="utf-8">) on math-heavy pages
Key Takeaways
Four methods all render ∞
∞ ∞ ∞For CSS stylesheets, use the escape in the content property
\221EUnicode U+221E belongs to the Mathematical Operators block (U+2200–U+22FF)
Prefer ∞ for readability in HTML source
Next: Information Source
❓ Frequently Asked Questions
∞ (hex), ∞ (decimal), ∞ (named), or \221E in CSS content. All produce ∞.U+221E (INFINITY). Mathematical Operators block (U+2200–U+22FF). Hex 221E, decimal 8734. Named entity: ∞. Used for limits, infinite sets, and unbounded quantities.∞, ∞, or ∞) go in markup. The CSS escape \221E belongs in stylesheets, typically in the content property of pseudo-elements. Both render ∞.∞ is the named HTML entity for ∞ (infinity). It is part of the HTML5 entity set and is well supported in modern browsers.Explore More HTML Entities!
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