\begin{article}

Getting Started with FormaTeX

Learn how to compile LaTeX documents to PDF in seconds using the FormaTeX API — no TeX Live installation required.

Mar 23, 2026·4 min read·

tutorialapigetting-started

FormaTeX gives you a REST API that accepts LaTeX source and returns a compiled PDF. No 4 GB TeX Live install, no version mismatches, no maintenance — just POST and receive.

This guide walks through creating an API key, compiling your first document, and handling errors correctly.

Prerequisites#

You need:

• A FormaTeX account (sign up free) — or try the Playground first without creating an account
• An API key from the dashboard
• curl or any HTTP client

Creating Your API Key#

After signing up, navigate to Dashboard → API Keys and click New Key. Give it a name — my-first-key works — and copy the raw key shown immediately. It is displayed only once.

Your First Compilation#

Send your LaTeX source as a JSON body with the latex field:

curl -X POST https://api.formatex.io/api/v1/compile \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "latex": "\\documentclass{article}\\begin{document}Hello, FormaTeX!\\end{document}",
    "engine": "pdflatex"
  }' \
  --output hello.pdf

The response is a raw PDF binary written directly to hello.pdf. That is the entire integration for simple documents.

Two response headers are always included on success:

Choosing an Engine#

FormaTeX supports four LaTeX engines:

The Free plan includes pdflatex. Pro, Max, and Enterprise plans unlock all four engines.

Handling Errors#

When compilation fails, the API returns a 422 status with a JSON body containing the full TeX log:

{
  "success": false,
  "error": "compilation failed",
  "log": "! Undefined control sequence.\nl.5 \\badcommand\n...",
  "duration": 843,
  "diagnostics": []
}

The log field is the raw TeX compiler output — it tells you exactly where the error is. Common errors and fixes:

• Undefined control sequence — typo in a command or missing \usepackage
• File not found — multi-file documents need all sources included in the request
• Overfull \hbox — warning only; the PDF still compiles and is returned
• Unicode characters with pdflatex — switch to xelatex or use Smart Compile with engine: "auto"

Using TypeScript#

Call the API directly with fetch:

const response = await fetch("https://api.formatex.io/api/v1/compile", {
  method: "POST",
  headers: {
    "X-API-Key": process.env.FORMATEX_API_KEY!,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    latex: latexSource,
    engine: "pdflatex",
  }),
});

if (!response.ok) {
  const error = await response.json();
  throw new Error(error.log ?? error.error);
}

const pdfBuffer = await response.arrayBuffer();

Tip: Store your API key in an environment variable, never in source code. The dashboard lets you set per-key expiration dates and revoke keys instantly.

Requesting a JSON Response#

By default the API streams the raw PDF binary. If you prefer a JSON envelope (e.g., to embed the PDF as base64 in an API response), pass Accept: application/json:

curl -X POST https://api.formatex.io/api/v1/compile \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -d '{"latex": "\\documentclass{article}\\begin{document}Hello\\end{document}", "engine": "pdflatex"}'

The JSON response looks like:

{
  "success": true,
  "pdf": "<base64-encoded PDF>",
  "jobId": "01J...",
  "engine": "pdflatex",
  "duration": 512,
  "sizeBytes": 14832,
  "diagnostics": []
}

Next Steps#

• Try the Playground — compile LaTeX instantly without creating an account
• Browse the API reference for the full endpoint schema
• Learn about Smart Compile — AI-powered error fixing for documents that fail to compile
• Use async compilation for long-running documents with webhook callbacks
• Explore engine comparisons to pick the right engine for your document

# That's it. Ship PDFs.
curl -X POST https://api.formatex.io/api/v1/compile \
  -H "X-API-Key: $FORMATEX_KEY" \
  -d '{"latex":"...","engine":"pdflatex"}' \
  --output result.pdf

\related{posts}

tutorialapiautomation

Automating Academic Paper PDFs with the LaTeX API

Academic papers, theses, and scientific reports all require LaTeX. Here is how to automate PDF generation for academic documents using the FormaTeX API in your research pipeline.

May 30, 2026·5 min read

tutorialapi

LaTeX PDF Generation in Node.js and TypeScript

Generate professional PDFs from LaTeX in Node.js — no system dependencies, no temp files, just an API call. Full TypeScript client with error handling and Next.js integration.

May 29, 2026·5 min read

tutorialapi

LaTeX Security Risks: What Happens When You Run pdflatex on Your Server

LaTeX is Turing-complete and can execute shell commands, read files, and make network requests. Here is what you are exposing when you run user-supplied LaTeX without a sandbox.

May 16, 2026·5 min read