Character
Σ
Unicode
U+03A3HTML named
ΣHTML decimal
ΣLaTeX
\SigmaSigma Symbol (σ) — Copy & Paste
Grab the sigma greek symbol in one click. Pronunciation: SIG-muh.
ΣUpper
σLower
ςFinal sigma (word-final)
Technical reference
Unicode, HTML entities, and LaTeX — tap the icon beside any value.
Character
σ
Unicode
U+03C3HTML named
σHTML decimal
σLaTeX
\sigmaCharacter
ς
Unicode
U+03C2HTML named
ςHTML decimal
ςLaTeX
\varsigmaCommon uses in science & math
Summation & standard deviation
Σ is the summation sign; σ commonly denotes standard deviation or stress in mechanics.
Conductivity & Pauli matrices
Physics uses σ for conductivity and for Pauli matrices; chemistry may use σ bonds.
How to type Sigma
Windows
Grab Σ for sums and σ for standard deviation from this page.
macOS
Use this page; Character Viewer lists both sigma forms.
Word & Google Docs
Σ and σ paste into Excel headers and stats assignments.
Prefer a full walkthrough? Read how to type Greek letters.
Related Greek letters
Sigma FAQ
When do I use ς instead of σ?
In Greek words, ς is the final form at the end of a word. In math, σ is almost always used.
How do I write a sum?
Grab Σ and write limits in your editor or use LaTeX \sum for professional typesetting.