free-symbols

Surface Integral Symbol

∯ denotes a surface integral in mathematics and related technical writing.

U+222F

The symbol ∯ is commonly read as “surface integral.” It’s used to express integrating a quantity over a surface rather than along a line or over a volume. Below you’ll find practical examples and copy options for documents and code.

Surface Integral Symbol Meaning

∯ (Unicode name: SURFACE INTEGRAL, code point U+222F) represents the operation of a surface integral. In mathematics and physics, it’s used when you integrate a function or expression over a two-dimensional surface in space. This is especially common in vector calculus, where surface integrals appear in formulas for flux and in theorems that relate surface behavior to volume or boundary quantities. In typeset equations, ∯ often pairs with an integrand (what you integrate) and a surface description (such as a surface S) to specify exactly where the integration happens.

Common uses

  • Writing vector calculus formulas involving flux across a surface
  • Expressing integrals over curved surfaces in physics notes
  • Labeling mathematical steps in textbooks and lecture slides
  • Formatting equation text in academic papers and reports
  • Rendering symbols in code or documentation that supports Unicode math

Examples

∯ Surface Integral — Symbol Info & Copy

  • ∯_S f dS
  • ∯_S \\mathbf{F} \\cdot d\\mathbf{A}
  • The total flux is given by ∯ over S.
  • Compute ∯_S g(x,y,z) dS for the surface.
  • Evaluate ∯_S (∇h · n) dS.

Variations

Ready to copy

Technical codes

UnicodeU+222F
HTML Entity∯
HTML Code∯
CSS\222F

FAQ

What does the Surface Integral symbol mean?

∯ (Unicode name: SURFACE INTEGRAL, code point U+222F) represents the operation of a surface integral. In mathematics and physics, it’s used when you integrate a function or expression over a two-dimensional surface in space. This is especially common in vector calculus, where surface integrals appear in formulas for flux and in theorems that relate surface behavior to volume or boundary quantities. In typeset equations, ∯ often pairs with an integrand (what you integrate) and a surface description (such as a surface S) to specify exactly where the integration happens.

What is the Unicode name of ∯?

The Unicode name is “SURFACE INTEGRAL,” with code point U+222F.

How can I copy the ∯ symbol?

Copy it directly as “∯”, or use the HTML entity “∯”, the CSS escape “\\222F”, or the JavaScript escape “\\u{222F}”.

When should I use ∯ instead of ∫ or ∬?

Use ∯ for integrating over a surface. Use ∫ for line (1D) integrals and ∬ for integrals over regions (often 2D) depending on the context.

Does ∯ work in plain text and code?

It usually works wherever the font and Unicode rendering are supported. If needed, you can insert it using the provided HTML/CSS/JavaScript escapes.