∮
Unicode
U+222ELaTeX
\ointHTML entity
HTML decimal
∮MathML
<mo>∮</mo>Semantic identity and intent
Characters to distinguish
- ∞ — Infinity
- e — Euler’s Number
- ∑ — Summation
Use ∮ in the right format
Meaning and usage
Represents an integral around a closed curve or contour.
Specify contour orientation and integrand.
Pronunciation: contour integral
Formula examples
\oint_C f(z)\,dzHow to type Contour Integral
- Windows
- Open Character Map and search by name or Unicode U+222E.
- macOS
- Open Character Viewer with Control–Command–Space and search by the symbol name.
- Microsoft Word
- In an equation, type \oint and press Space when Word supports the command.
- 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 \oint.
- 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; Specify contour orientation and integrand.
- For plain text, copy ∮ as U+222E; for structured equations, use \oint in math mode. A look-alike glyph or image can break search, accessibility, or parsing when the intended character is Contour Integral.
When to use ∮
- Use ∮ in plain text when a Unicode character is appropriate and the destination preserves U+222E.
- Use \oint in an equation editor when mathematical spacing or structure matters.
- Define the local meaning when Contour Integral is used in calculus, differential equations with a field-specific convention.
Look-alikes and related characters
- ∞ — Infinity
- e — Euler’s Number
- ∑ — Summation
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 Contour Integral to a finished equation
- Copy the characterUse ∮ in plain text when Unicode is accepted.
- Choose a structured formatUse
\ointfor LaTeX or the MathML snippet for accessible web equations. - 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 Contour Integral 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
- The Unicode StandardUnicode Consortium — Character identity, encoding, names, and conformance.
- Unicode Character Code ChartsUnicode Consortium — Code points and official character charts.
- Unicode Technical Report #25: Unicode Support for MathematicsUnicode Consortium — Mathematical character usage, variants, and notation support.
- LaTeX Project DocumentationThe LaTeX Project — LaTeX syntax, authoring model, and official documentation links.
- MathML CoreW3C — Semantic web mathematics elements and browser behavior.
Frequently asked questions
What does the Contour Integral symbol mean?
Represents an integral around a closed curve or contour.
What is the LaTeX command for ∮?
Use \oint in a compatible math environment.
Can I copy ∮ as Unicode?
Yes. Use the copy button above to copy the Unicode character directly.