w:caps (All Capitals)

Displays all lowercase letters in the run as uppercase without altering the stored text.

Parent elements

w:rPr

Description

w:caps displays all lowercase letters in the run as uppercase characters. It is an on/off toggle property defined in ECMA-376 Part 1 §17.3.2.4.

Unlike converting text to uppercase, w:caps does not change the stored text — the underlying characters remain in their original case. Only the rendered glyphs are uppercased. This means a spell-checker still uses the original mixed-case text.

w:smallCaps and w:caps are mutually exclusive; if both are set, w:caps takes precedence.

Attributes

Attribute	Type	Possible Values	Description
`w:val`	`ST_OnOff`	`true`, `1`, `on` (enabled) / `false`, `0`, `off` (disabled). Omitting the attribute is equivalent to `true`.	Toggles All Caps on or off.

Examples

<w:r>
  <w:rPr>
    <w:caps/>
  </w:rPr>
  <w:t>hello world</w:t>
</w:r>

// Stored as lowercase, rendered as HELLO WORLD
new Run(
  new RunProperties(new Caps()),
  new Text("hello world"));

<!-- Cancel caps from parent style -->
<w:rPr>
  <w:caps w:val="false"/>
</w:rPr>

new RunProperties(new Caps { Val = false });

Notes

Content unchanged: stored as original case, rendered as uppercase.
Spell-checking uses original text, not rendered form.
Toggle property: w:val="false" cancels caps from parent.
Mutually exclusive with w:smallCaps (caps takes precedence).
Search and copy use original text, not rendered uppercase.
Works consistently across Office versions.