Rendering Markdown to HTML with Syntax Highlighting
Markup
Why Server-Side Markdown Rendering?
Rendering Markdown in the browser is fine for simple cases, but server-side rendering has real advantages:
- SEO — search engines index the rendered HTML, not raw Markdown
- Security — XSS is sanitised centrally, not per-client
- Consistency — the same output regardless of which Markdown library the client uses
- Syntax highlighting — Pygments produces accurate, theme-able code blocks
Calling the API
curl -X POST https://api.toolkitapi.io/v1/convert/markdown-to-html \
-H "X-API-Key: $API_KEY" \
-H "Content-Type: application/json" \
-d '{"markdown": "# Hello\n\nThis is **bold** text."}'
Response:
{
"html": "<h1>Hello</h1>\n<p>This is <strong>bold</strong> text.</p>"
}
Supported Extensions
| Extension | What it enables |
|---|---|
fenced_code |
Triple-backtick code blocks |
tables |
GFM-style pipe tables |
toc |
[TOC] placeholder generates a table of contents |
footnotes |
[^1] footnote syntax |
strikethrough |
~~deleted~~ text |
Pass the extensions you need in the request body:
{
"markdown": "...",
"extensions": ["tables", "fenced_code", "toc"]
}
Syntax Highlighting
When fenced_code is enabled, you can specify a language on the opening fence:
```python
def hello():
return "world"
```
The API applies Pygments highlighting and returns a <div class="highlight"> block
with inline CSS classes — ready to style with any Pygments CSS theme.
Storing Rendered HTML
If your content rarely changes, store the rendered HTML in your database alongside the raw Markdown. On read, serve the cached HTML. On write, call the API to re-render. This avoids repeated API calls and keeps rendering costs near zero.