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Aug 08, 2026
HTML Entity Detail
HTML Entity - Sigma
Sigma is a uppercase Greek alphabet letters used in mathematics, science, and engineering. This HTML entity enables web developers to display this character reliably across all browsers without encoding issues.
Symbol preview
Σ
Unicode
U+03A3;
HTML entity
Σ
CSS code
\03A3
Usage Examples
Use this HTML entity in mathematical and scientific notation. For example, Σ for summation, Π for product, Δ for difference.
Related Entities
Common Mistakes
⚠️
Mistake: Confusing Σ (capital sigma / summation) with ∑ (summation symbol)
Fix: Both Σ and ∑ are used for summation. In modern notation, ∑ is more common for the summation operator. Σ is the capital Greek letter.
⚠️
Mistake: Using S instead of Σ for summation notation
Fix: Use Σ or ∑ (not S) for summation in mathematical notation. The Latin letter S is not a valid substitute for the Greek sigma.
Sigma
Select any code to highlight it before copying.
Category: Greek Alphabet - Capital Letters
| Unicode | U+03A3; |
|---|---|
| Hex Code | Σ |
| HTML Code | Σ |
| HTML Entity | Σ |
| CSS Code | \03A3 |
| Windows Shortcut | |
| Mac Shortcut | |
HTML code example
CSS code example
Last updated: 17 Aug 2026
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