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Flatten PDF API

Convert fillable PDF forms into static, non-editable documents.

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1const fs = require("fs/promises");23(async () => {4  const form = new FormData();56  const bytes = await fs.readFile("YOUR_FILE.pdf");7  const file = new File([bytes], "YOUR_FILE.pdf", { type: "application/pdf" });8  form.append("file", file);910  form.append("jsonResponse", "false");11  form.append("metadata", JSON.stringify({12    author: "John Doe",13    documentType: "Contract",14  }));1516  const res = await fetch("https://api.pdfgate.com/forms/flatten", {17    method: "POST",18    body: form,19    headers: { Authorization: "Bearer YOUR_API_KEY" },20  });2122  if (res.status === 201) {23    const buf = Buffer.from(await res.arrayBuffer());24    await fs.writeFile("flattened.pdf", buf);25  } else {26    const text = await res.text();27    console.error(text);28  }29})();

720,000+Documents processed monthly

1,300+Developers using the API

1.6sAverage processing time

99.9%Uptime

The Flatten PDF API allows you to convert interactive PDF form fields into static content as part of an automated document workflow. It is designed for scenarios where filled forms need to be finalized before being shared, stored, or printed.

Flattening a PDF ensures that form values become part of the document layout and can no longer be modified. This is commonly used after form submission to preserve the data exactly as entered and to prevent further changes to the document.

This endpoint can be used on its own or combined with other PDFGate endpoints. A typical workflow includes generating a PDF form, collecting user input, flattening the form to lock in the data, and optionally applying security or compression before distribution.

The Flatten PDF API is well suited for SaaS platforms, internal tools, and document automation systems that require consistent, repeatable form finalization without relying on manual PDF processing.