Σ
Capital Sigma in Mathematics
In Mathematics, the Capital Sigma symbol (Σ) is commonly used. Learn how to copy and use it in your technical documents.
Unicode
U+03A3
HTML Entity
Σ
LaTeX Sequence
\capitalsigma
Primary Field
MathematicsMathematics Application
Capital Sigma is the summation operator: Σ tells you to add a sequence of terms, with the index and limits written below and above it. It is one of the most common symbols in statistics, calculus and computer science.
How to type Sigma (capital) (Σ)
- Fastest: click Σ on the keyboard above — it copies to your clipboard, ready to paste into Word, Google Docs, email or a forum.
- Unicode: the code point is shown in the panel above; on Windows you can also use Alt‑X after the hex code in Word.
- LaTeX: use the command shown above inside math mode.
- Anywhere: because it’s standard Unicode, it keeps its exact form across apps and devices.
Frequently asked questions
How do I read a Σ expression?
Add every term as the index runs from the value below Σ to the value above it.
Is Σ the same as σ?
No — capital Σ means ‘sum’; lowercase σ is standard deviation.
Write mathematical and scientific expressions
Need to pair this symbol with other operators?