Sigma Symbol (σ)
Copy the Sigma symbol σ to your clipboard, and see its Unicode code point, HTML entity, LaTeX command and how to type it on any device.
What does σ mean?
Lowercase sigma is the standard deviation in statistics (a measure of spread), mechanical stress in engineering, electrical conductivity, and surface charge density in physics. Its capital form Σ is the summation operator. σ is the lowercase form of Sigma, letter 18 of 24 in the Greek alphabet (pronounced SIG-ma). Its capital counterpart is Σ. In science and maths it is used for: Summation (Σ), standard deviation and stress (σ).
Codes and properties
| Character | σ |
|---|---|
| Unicode name | GREEK SMALL LETTER SIGMA |
| Code point | U+03C3 |
| Decimal | 963 |
| Unicode block | Greek and Coptic |
| HTML entity | σ · σ · σ |
| CSS | \03C3 |
| JavaScript / JSON | \u03C3 |
| Python | \u03C3 or \N{GREEK SMALL LETTER SIGMA} |
| UTF-8 bytes | CF 83 |
| LaTeX | \sigma |
How to type σ
- Copy & paste: press the Copy button above, then paste σ anywhere — Word, Google Docs, email, chat or code.
- Windows (Word, WordPad, Outlook): type
03C3then press Alt+X. In any app, Win+. opens the symbol panel. - Mac: switch to the Unicode Hex Input keyboard, hold Option and type
03C3; or press Ctrl+Cmd+Space and search “greek small letter sigma”. - Linux (GTK/IBus): press Ctrl+Shift+U, type
03c3, then Space. - HTML:
σrenders as σ. - LaTeX:
\sigmain math mode (amssymb package for some symbols).
Frequently asked questions
What does σ mean in statistics?
Standard deviation — how far values typically fall from the mean. About 68% of a normal distribution lies within ±1σ.
How is σ different from Σ?
Lowercase σ is standard deviation (or stress); capital Σ means ‘sum of’.
How do I type σ on Windows?
In Microsoft Word type 03C3 and press Alt+X. In any app press Win+. to open the symbol panel, or copy σ from this page.
What is the HTML code for σ?
Use σ or σ (hex) or σ (decimal).
What is the LaTeX command for σ?
Use \sigma in math mode.