Skip to main content
Sarde
On this page

Math

Render inline and block LaTeX math expressions using KaTeX

Math expressions render LaTeX notation using KaTeX. Inline expressions use single dollar signs. Display (block) expressions use double dollar signs.

Inline math

Wrap an expression in single $ delimiters to render it inline with the surrounding text:

Markdown
The quadratic formula is $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$ where $a \neq 0$.

→ The formula renders inline as typeset math, matching the line height of the surrounding paragraph.

Display math

Wrap an expression in double $$ delimiters on their own lines for a centered, full-width block:

Markdown
$$
E = mc^2
$$

→ The equation appears centered on its own line in a larger font.

Multi-line expressions are supported:

Markdown
$$
\int_0^\infty e^{-x^2} dx = \frac{\sqrt{\pi}}{2}
$$

Single-line display math is also valid:

Markdown
$$ F = ma $$

KaTeX rendering

KaTeX assets (CSS, JS, fonts) are automatically injected on pages that contain math markup. The KaTeX plugin detects class="sarde-math" in the rendered HTML and appends the required scripts and stylesheet.

No configuration is needed. KaTeX is enabled by default via markdown.katex: true in sarde.yaml.

To force KaTeX assets on every page (useful when math is loaded dynamically):

YAML
plugins:
  config:
    katex:
      always: true

To disable math rendering entirely:

YAML
markdown:
  katex: false

Edge cases

  • A single $ followed by a digit on the closing side (e.g., costs $9 and $29) is not treated as math. The parser avoids false matches with currency amounts.
  • Empty expressions ($$) are ignored.
  • LaTeX characters ({, }, &, \) are preserved for KaTeX. Only < and > are HTML-escaped to prevent injection.
  • Display math can interrupt a paragraph (no blank line required before $$).

See the KaTeX plugin for runtime asset injection and configuration.