w:oMath (Office Math)

Toggle property in rPr that marks a run as containing Office Math content, applying math-specific formatting.

Parent elements

w:rPr

Description

w:oMath is a toggle property in w:rPr that marks the run as math content. When active, the processor applies math-specific rendering rules (Office Math fonts, math spacing, etc.) to the run’s text, even if the text does not appear inside an <m:oMath> element.

It is defined in ECMA-376 Part 1 §17.3.2.25.

Note: For mathematical equations in modern OOXML documents, use the Office Math Markup Language (OMML) elements in the m: namespace (e.g. <m:oMath>, <m:r>, etc.) directly. w:oMath in w:rPr is a legacy signal that should rarely be authored manually.

Attributes

Attribute	Type	Possible Values	Description
`w:val`	`ST_OnOff`	`true`, `false`, `1`, `0`, `on`, `off`	Marks the run as math content. Omit to inherit.

Examples

<!-- Inline math content using OMML (preferred approach) -->
<m:oMathPara>
  <m:oMath>
    <m:r>
      <m:rPr><m:sty m:val="p"/></m:rPr>
      <m:t>E=mc</m:t>
    </m:r>
    <m:sSup>
      <m:e><m:r><m:t>2</m:t></m:r></m:e>
    </m:sSup>
  </m:oMath>
</m:oMathPara>

<!-- Using w:oMath as a run property flag (legacy) -->
<w:r>
  <w:rPr>
    <w:oMath/>
  </w:rPr>
  <w:t>x</w:t>
</w:r>

using DocumentFormat.OpenXml.Wordprocessing;

var run = new Run(
    new RunProperties(new OfficeMath()),
    new Text("x")
);

Notes

For full mathematical equation support, use OMML (m:oMath, m:r, etc.) — not w:oMath in w:rPr.
w:oMath in w:rPr is typically generated when Word converts between OMML and its internal representation.