> For the complete documentation index, see [llms.txt](https://docs.validationcloud.io/v1/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.validationcloud.io/v1/arc/trace-api/trace_call.md).

# trace\_call

Executes a new message call and returns a number of possible traces.

This method will use `80` [Compute Units](/v1/about/billing.md).

***

## **Parameters**

`blockNumber` - String - <mark style="color:red;">Required</mark> - The block number as a string in hexadecimal format or tags. The supported tag values include:

* `earliest` - For the earliest/genesis block
* `latest` for the latest mined block
* `safe` for the most recent secure block
* `finalized` for the most recent secure block accepted by more than 2/3 of validators

## **Returns**

`object` - object -The transaction trace result object

* `output` - string - The data returned as output encoded in hexadecimal format
* `stateDiff` - object - The altered Ethereum state due to execution of the given transaction, or null if not available
* `trace` - array - An array of basic trace objects for the given transaction containing:
  * `action` - object The ParityTrace action object containing call details
    * `from` - string - The address of the sender
    * `callType` - string - The type of method such as call, staticcall, delegatecall
    * `gas` - string - The gas provided by the sender, encoded as hexadecimal
    * `input` - string - The input data sent along with the transaction
    * `to` - string - The address of the receiver
    * `value` - string - The integer of the value sent with this transaction, encoded as hexadecimal
  * `result` - object - The execution result of the trace
    * `gasUsed` - string - The amount of gas used by this trace
    * `output` - string - The return value of the contract call, empty if no RETURN executed
  * `subtraces` - integer - The number of subtraces (internal calls) within this trace
  * `traceAddress` - array - The list of addresses where the call executed, including parent calls and order
  * `type` - string The type of the trace, such as call or create
* `vmTrace` - object - The full trace of the virtual machine's state during execution, including sub-calls, or null if not available

```bash
// Result
{
    "jsonrpc": "2.0",
    "id": 1,
    "result": {
      "output": "0x0000000000000000000000000000000000000000000000000000000000000001",
      "stateDiff": null,
      "trace": [
        {
          "type": "call",
          "action": {
            "from": "0x786d1ecc7ad626f48d6d95ccb2c0500e52e4a15b",
            "callType": "call",
            "gas": "0x2fa9c18",
            "input": "0xa9059cbb0000000000000000000000009406c483929bac16a41efae8665d8dab68c33eea0000000000000000000000000000000000000000000000000000000002fa2d30",
            "to": "0x20c0000000000000000000000000000000000000",
            "value": "0x0"
          },
          "result": {
            "gasUsed": "0x8a2e",
            "output": "0x0000000000000000000000000000000000000000000000000000000000000001"
          },
          "subtraces": 0,
          "traceAddress": []
        }
      ],
      "vmTrace": null
    }
  }
```

{% tabs %}
{% tab title="testnet" %}

```bash
curl https://testnet.arc.validationcloud.io/v1/<YOUR_API_KEY_HERE> \
    -X POST \
    -H "Content-Type: application/json" \
    -d '{"jsonrpc":"2.0","method":"trace_call","params":[{"from":"0x786d1ecc7ad626f48d6d95ccb2c0500e52e4a15b","to":"0x20c0000000000000000000000000000000000000","data":"0xa9059cbb000000000000
  0000000000009406c483929bac16a41efae8665d8dab68c33eea0000000000000000000000000000000000000000000000000000000002fa2d30"},["trace"],"latest"],"id":1}'

```

{% endtab %}
{% endtabs %}


---

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