Math symbol reference

Summation

Represents the sum of a sequence of terms.

UnicodeU+2211
LaTeX\sum
HTML entity∑
HTML decimal∑
MathML<mo>∑</mo>

Semantic identity and intent

Semantic type

operator

An operator, relation, connective, or notation mark whose meaning depends on its operands and context.

Primary search task

understand the operation or relation, see a valid example, and copy the correct notation

Calculus SymbolsAlgebra SymbolsInformation Theory Symbols

MathML token

<mo>

Use ∑ with the operand structure shown in the examples. Preserve grouping, limits, spacing, and evaluation order when converting between formats.

Characters to distinguish

  • ∏ — Product
  • ∫ — Integral

Use ∑ in the right format

Meaning and usage

Represents the sum of a sequence of terms.

Add lower and upper limits to specify the index range.

Pronunciation: summation

Formula examples

\sum_{i=1}^{n}i
\sum_{k=0}^{\infty}ar^k

How to type Summation

Windows
Use Character Map or enter U+2211 in a Unicode-aware app.
macOS
Open Character Viewer with Control–Command–Space and search by name.
Microsoft Word
Type \sum in an equation and press Space.
iPhone and iPad
Copy and paste ∑, or use a math/LaTeX app. The standard iOS keyboard may not expose every mathematical symbol.
Android
Copy and paste ∑, or use a math keyboard or LaTeX editor. Keyboard layouts vary by device and app.
Google Docs
For plain text, paste ∑ or use Insert → Special characters. For structured math, use the equation editor and verify \sum.
Excel
Paste ∑ into a cell or use Insert → Symbol when available. Ordinary cells preserve the character but do not interpret LaTeX commands.

Common mistakes

  • Check whether ∑ is acting as an operator, differential, index, or variable in the surrounding expression; Add lower and upper limits to specify the index range.
  • For plain text, copy ∑ as U+2211; for structured equations, use \sum in math mode. A look-alike glyph or image can break search, accessibility, or parsing when the intended character is Summation.

When to use ∑

  • Use ∑ in plain text when a Unicode character is appropriate and the destination preserves U+2211.
  • Use \sum in an equation editor when mathematical spacing or structure matters.
  • Define the local meaning when Summation is used in calculus, algebra, information theory with a field-specific convention.

Look-alikes and related characters

  • ∏ — Product
  • ∫ — Integral

Font and compatibility notes

Glyph shape can vary by font. Verify the code point after copying, and prefer LaTeX or MathML for structured equations.

Continue the workflow

From Summation to a finished equation

  1. Copy the characterUse ∑ in plain text when Unicode is accepted.
  2. Choose a structured formatUse \sum for LaTeX or the MathML snippet for accessible web equations.
  3. Edit or convertOpen the value in the editor or converter without retyping it.

Review and source notes

Quality tier: core

Last reviewed: 2026-07-26

Review method: Checked Summation against its Unicode identity, LaTeX representation, HTML serialization, MathML token, and copy-and-paste behavior.

Verified against: Unicode Standard, Unicode mathematical notation guidance, and established LaTeX/MathML syntax.

Reference sources

Frequently asked questions

What does the Summation symbol mean?

Represents the sum of a sequence of terms.

What is the LaTeX command for ∑?

Use \sum in a compatible math environment.

Can I copy ∑ as Unicode?

Yes. Use the copy button above to copy the Unicode character directly.

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