Sigma Symbol Copy and Paste Σ σ ς ∑

The Sigma symbol (Σ for uppercase, σ for lowercase) is a Greek letter widely used in mathematics and science. The uppercase (Σ) represents summation, indicating the sum of a series of terms, such as (Σxᵢ), which means adding up all the values of xᵢ. The lowercase (σ) is often used to represent standard deviation in statistics, or stress in physics and engineering. To input the symbol, use (Alt + 228) for Σ and (Alt + 229) for σ on Windows, (Control + Command + Space) on Mac, or copy-paste from a character map or Unicode (`U+03C3` for lowercase, `U+03A3` for uppercase). Click to copy and paste the Sigma symbol on this page.