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

<AgentInstructions>

## Submitting Feedback

If you encounter incorrect, outdated, or confusing documentation on this page, submit feedback:

POST https://docs.chainstack.com/feedback

```json
{
  "path": "/reference/arbitrum-debug-getrawheader",
  "feedback": "Description of the issue"
}
```

Only submit feedback when you have something specific and actionable to report.

</AgentInstructions>

# debug_getRawHeader | Arbitrum

Arbitrum API method that returns the RLP-encoded block header for a given block number or tag. Unlike `debug_getRawBlock`, this method returns only the header without transaction data, making it more efficient when only header information is needed.

<Note>
  Learn how to [deploy a node](/docs/debug-and-trace-apis#arbitrum) with the debug and trace API methods enabled.
</Note>

<Warning>
  This method is available for post-Nitro blocks only (block 22,207,815 and later). For pre-Nitro blocks, use the `arbtrace_*` methods instead.
</Warning>

<Check>
  **Get your own node endpoint today**

  [Start for free](https://console.chainstack.com/) and get your app to production levels immediately. No credit card required.

  You can sign up with your GitHub, X, Google, or Microsoft account.
</Check>

## Parameters

* `quantity or tag` — the block number in hex format or block tag (`latest`, `earliest`, `pending`, `safe`, `finalized`).

## Response

* `data` — the RLP-encoded block header as a hex string.

## `debug_getRawHeader` code examples

<CodeGroup>
  ```javascript ethers.js theme={"system"}
  const ethers = require('ethers');
  const NODE_URL = "YOUR_CHAINSTACK_ENDPOINT";
  const provider = new ethers.JsonRpcProvider(NODE_URL);

  const debugGetRawHeader = async (block) => {
    const result = await provider.send("debug_getRawHeader", [block]);
    console.log(result);
  };

  debugGetRawHeader("latest");
  ```

  ```python web3.py theme={"system"}
  from web3 import Web3
  node_url = "YOUR_CHAINSTACK_ENDPOINT"
  web3 = Web3(Web3.HTTPProvider(node_url))

  result = web3.provider.make_request('debug_getRawHeader', ["latest"])
  print(result)
  ```
</CodeGroup>

## Use case

The `debug_getRawHeader` method is useful when you need to inspect or verify block headers without the overhead of retrieving full block data. This is particularly valuable for light client implementations, header chain verification, and tools that need to extract specific header fields like the state root, receipts root, or gas used from the raw RLP encoding.


## OpenAPI

````yaml /openapi/arbitrum_node_api/debug_and_trace/debug_getRawHeader.json POST /66f812de2a6724a75a51f60dd6f2a154
openapi: 3.0.0
info:
  title: Chainstack Node API
  version: 1.0.6
  description: >-
    This is an API for interacting with a Chainstack node using the
    debug_getRawHeader method.
servers:
  - url: https://nd-954-882-037.p2pify.com
security: []
paths:
  /66f812de2a6724a75a51f60dd6f2a154:
    post:
      tags:
        - upload
      summary: debug_getRawHeader
      operationId: debugGetRawHeader
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                id:
                  type: integer
                  default: 1
                jsonrpc:
                  type: string
                  default: '2.0'
                method:
                  type: string
                  default: debug_getRawHeader
                params:
                  type: array
                  items:
                    type: string
                    title: Block
                    description: >-
                      Block number in hex format or tag (latest, earliest,
                      pending, safe, finalized).
                  default:
                    - latest
      responses:
        '200':
          description: Returns the RLP-encoded block header.
          content:
            application/json:
              schema:
                type: object
                properties:
                  jsonrpc:
                    type: string
                  id:
                    type: integer
                  result:
                    type: string

````