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Aug 08, 2026
HTML Entity Detail
HTML Entity - Alef Symbol
Alef Symbol is a letterlike mathematical symbols representing number sets and special functions. This HTML entity enables web developers to display this character reliably across all browsers without encoding issues.
Symbol preview
ℵ
Unicode
U+2135
HTML entity
ℵ
CSS code
\2135
Usage Examples
Use this HTML entity in mathematical notation for number sets like ℝ (real numbers) and ℕ (natural numbers), and physics constants.
Related Entities
Common Mistakes
⚠️
Mistake: Confusing ℵ (aleph) with a stylized Hebrew letter
Fix: The aleph symbol ℵ is specifically used in set theory for transfinite cardinal numbers. It is not a decorative character.
⚠️
Mistake: Using infinity ∞ instead of aleph ℵ for cardinalities
Fix: Use ℵ for cardinalities of infinite sets (ℵ₀, ℵ₁). Use ∞ for limits and unbounded quantities. They represent different mathematical concepts.
Alef Symbol
Select any code to highlight it before copying.
Category: Letterlike Symbols
| Unicode | U+2135 |
|---|---|
| Hex Code | ℵ |
| HTML Code | ℵ |
| HTML Entity | ℵ |
| CSS Code | \2135 |
| Windows Shortcut | |
| Mac Shortcut | |
HTML code example
CSS code example
Last updated: 17 Aug 2026
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