> ## Documentation Index
> Fetch the complete documentation index at: https://docs.vortexpdf.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Output encoding

> Control how the PDF is encoded in the API response by specifying binary or base64 format

The `output_encoding` parameter allows you to specify how the PDF should be encoded in the API response.

## Overview

When rendering a PDF synchronously, you can choose how the generated PDF is encoded in the response. The `output_encoding` parameter lets you specify whether to return raw binary data or a base64-encoded string.

## Parameter details

<ResponseField name="output_encoding" type="enum<string>" default="binary">
  Specifies how the PDF should be encoded in the API response

  Available options: `binary`, `base64`
</ResponseField>

## Usage

```javascript theme={null}
{
  "parts": "https://example.com",
  "output_encoding": "binary" // or "base64"
}
```

## Behavior

* **`binary`**: Returns the PDF as raw binary data in the response body. This is the default behavior.
* **`base64`**: Returns the PDF as a base64-encoded string in the response body.

## Use cases

This parameter is particularly useful for:

1. **Direct downloads**: Use `binary` when you want to directly download or stream the PDF to the client.

2. **API integration**: Use `base64` when integrating with systems that expect base64-encoded data or when you need to include the PDF in a JSON response.

3. **Browser compatibility**: Use `base64` when working with JavaScript in browsers where handling binary data might be challenging.

## Example

### Binary response handling (Node.js)

```javascript theme={null}
fetch("https://vortexpdf.com/api/v1/renderers/pdf", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    Authorization: "Bearer YOUR_API_KEY",
  },
  body: JSON.stringify({
    parts: "https://example.com",
    output_encoding: "binary",
  }),
})
  .then((response) => response.arrayBuffer())
  .then((buffer) => {
    // Handle binary PDF data
    fs.writeFileSync("output.pdf", Buffer.from(buffer));
  });
```

### Base64 response handling (JavaScript)

<Warning>
  Never include your API key directly in client-side code as it can be exposed
  to users. Always use a backend service to make API calls that require
  authentication.
</Warning>

```javascript theme={null}
fetch("https://vortexpdf.com/api/v1/renderers/pdf", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    Authorization: "Bearer YOUR_API_KEY",
  },
  body: JSON.stringify({
    parts: "https://example.com",
    output_encoding: "base64",
  }),
})
  .then((response) => response.text())
  .then((base64String) => {
    // Create a data URL for embedding in HTML or downloading
    const dataUrl = `data:application/pdf;base64,${base64String}`;

    // Create a download link
    const link = document.createElement("a");
    link.href = dataUrl;
    link.download = "document.pdf";
    link.click();
  });
```