The Greek Capital Letter Sigma symbol (Σ). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Greek Letters.
The quickest way is to copy Σ from this page and paste it anywhere. You can also insert it with its Unicode, HTML, or alt code listed above.
Σ is U+03A3 (decimal 931).
Use Σ in HTML to render Σ on a web page.
On Windows you can type it with Alt+931 (hold Alt and enter the number on the numeric keypad).
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