Code to Image API
Generate beautiful code snippet images with syntax highlighting via html2png.dev.
How It Works
- Write HTML with syntax-highlighted code (use Shiki or similar)
- Style with Tailwind CSS or custom CSS
- Send to
/api/convertendpoint - Get a shareable image URL
Endpoint
POST https://html2png.dev/api/convert
Example
curl -X POST "https://html2png.dev/api/convert?width=800&deviceScaleFactor=2" \
-H "Content-Type: text/html" \
-d '<!DOCTYPE html>
<html>
<head>
<script src="https://cdn.tailwindcss.com"></script>
<link href="https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;700&display=swap" rel="stylesheet">
<style>
.shiki { background: transparent !important; }
.line::before {
content: attr(data-line);
width: 2rem;
margin-right: 1rem;
display: inline-block;
text-align: right;
color: rgba(128,128,128,0.4);
}
</style>
</head>
<body class="p-12" style="background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);">
<div class="bg-white rounded-xl shadow-2xl overflow-hidden">
<div class="flex items-center gap-2 px-4 py-3 border-b border-gray-200">
<div class="w-3 h-3 rounded-full bg-red-400"></div>
<div class="w-3 h-3 rounded-full bg-yellow-400"></div>
<div class="w-3 h-3 rounded-full bg-green-400"></div>
<span class="ml-2 text-xs text-gray-500 font-mono">hello.js</span>
</div>
<pre class="p-6 font-mono text-sm leading-relaxed"><code class="language-javascript"><span style="color:#D73A49">function</span> <span style="color:#6F42C1">greet</span>(<span style="color:#24292E">name</span>) {
<span style="color:#D73A49">return</span> <span style="color:#032F62">`Hello, ${name}!`</span>;
}
<span style="color:#6F42C1">console</span>.<span style="color:#6F42C1">log</span>(<span style="color:#6F42C1">greet</span>(<span style="color:#032F62">"World"</span>));</code></pre>
</div>
</body>
</html>'
Key Elements
Syntax Highlighting:
- Use Shiki (
shiki.style) or highlight.js for token coloring - Inline styles work best for standalone images
Window Chrome:
- Traffic light dots (red, yellow, green)
- Filename in title bar
- Rounded corners, shadows
Typography:
- JetBrains Mono or Fira Code for code
- Inter or system fonts for UI elements
- Line numbers optional
Backgrounds:
- Gradient backgrounds for the container
- White or dark code window
- Glassmorphism effects
Shiki Integration
For server-side syntax highlighting:
import { createHighlighter } from "shiki";
const highlighter = await createHighlighter({
themes: ["github-light"],
langs: ["javascript", "python", "rust"],
});
const html = highlighter.codeToHtml(code, {
lang: "javascript",
theme: "github-light",
});
Tips
- Use
deviceScaleFactor=2for crisp text - Add
delay=500if using web fonts - Container width should match
widthparam - Use
omitBackground=truefor transparent PNGs
Rate Limits
50 requests/hour per IP.