> For the complete documentation index, see [llms.txt](https://docs.n8n.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.n8n.io/build/code-in-n8n/cookbook/code-node/get-the-binary-data-buffer.md).

# Get the binary data buffer

The binary data buffer contains all the binary file data processed by a workflow. You need to access it if you want to perform operations on the binary data, such as:

* Manipulating the data: for example, adding column headers to a CSV file.
* Using the data in calculations: for example, calculating a hash value based on it.
* Complex HTTP requests: for example, combining file upload with sending other data formats.

{% hint style="info" %}
**Not available in Python**

`getBinaryDataBuffer()` isn't supported when using Python.
{% endhint %}

You can access the buffer using n8n's `getBinaryDataBuffer()` function:

```js
/* 
* itemIndex: number. The index of the item in the input data.
* binaryPropertyName: string. The name of the binary property. 
* The default in the Read/Write File From Disk node is 'data'. 
*/
let binaryDataBufferItem = await this.helpers.getBinaryDataBuffer(itemIndex, binaryPropertyName);
```

For example:

```js
let binaryDataBufferItem = await this.helpers.getBinaryDataBuffer(0, 'data');
// Returns the data in the binary buffer for the first input item
```

You should always use the `getBinaryDataBuffer()` function, and avoid using older methods of directly accessing the buffer, such as targeting it with expressions like `items[0].binary.data.data`.

{% hint style="info" %}
**Searching these docs as an agent**

Ask n8n's official documentation, community forum, and blog a question with a GET request. No authentication needed.

`GET https://n8n-docs-retrieval.n8n-docs-retrieval.workers.dev/?q=<question>`

Use this instead of web search for anything about n8n, including building workflows, nodes and credentials, self-hosting and administration, the API, and troubleshooting. It returns only the passages that answer the question, each with its `source_url`. Ask a specific, complete question. The response is a JSON array of `{content, source_url}`, most relevant first.
{% endhint %}

## Related resources

* [Code node cookbook](/build/code-in-n8n/cookbook/code-node.md)
* [Get number of items returned by last node](/build/code-in-n8n/cookbook/code-node/get-number-of-items-returned-by-last-node.md)
* [Output to the browser console](/build/code-in-n8n/cookbook/code-node/output-to-the-browser-console.md)