# arbtrace_replayBlockTransactions

> For the complete documentation index, see [llms.txt](/docs/llms.txt).

POST https://arb-mainnet.g.alchemy.com/v2/{apiKey}

Replays all transactions in the specified block and returns the requested trace types for each transaction. This is an Arbitrum-specific tracing method that works for pre-Nitro blocks (before block 22,207,815). For post-Nitro blocks, use Geth debug_* methods.


Reference: https://www.alchemy.com/docs/chains/arbitrum/arbitrum-api-endpoints/arbtrace-replay-block-transactions

## Parameters

| Name | Type | Required | Description |
|------|------|----------|-------------|
| Block number | string or enum | Yes | The block number as a hexadecimal string, or a block tag such as "latest", "earliest", or "pending".  |
| Trace types | enum[] | Yes | Array of trace types to return. Valid values: "trace", "vmTrace", "stateDiff".  |

## Result

**Block transaction traces** (object[]): An array of trace results, one per transaction in the block.

## Example

### Request

```json
{
  "jsonrpc": "2.0",
  "method": "arbtrace_replayBlockTransactions",
  "params": [
    "0x152DD07",
    [
      "trace"
    ]
  ],
  "id": 1
}
```

### Response

```json
{
  "jsonrpc": "2.0",
  "result": [
    {
      "output": "0x",
      "stateDiff": null,
      "trace": [
        {
          "action": {
            "callType": "call",
            "from": "0x00000000000000000000000000000000000a4b05",
            "gas": "0x0",
            "input": "0x",
            "to": "0xa4b05fffffffffffffffffffffffffffffffffff",
            "value": "0x0"
          },
          "result": {
            "gasUsed": "0x0",
            "output": "0x"
          },
          "subtraces": 0,
          "traceAddress": [],
          "type": "call"
        }
      ],
      "vmTrace": null
    }
  ],
  "id": 1
}
```

## Code Examples

### cURL

```bash
curl --request POST \
  --url https://arb-mainnet.g.alchemy.com/v2/docs-demo \
  --header 'Content-Type: application/json' \
  --data '{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "arbtrace_replayBlockTransactions",
  "params": [
    "0x152DD07",
    [
      "trace"
    ]
  ]
}'
```

### JavaScript

```javascript
const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({
    jsonrpc: '2.0',
    id: 1,
    method: 'arbtrace_replayBlockTransactions',
    params: ['0x152DD07', ['trace']]
  })
};

fetch('https://arb-mainnet.g.alchemy.com/v2/docs-demo', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));
```

### Python

```python
import requests

url = "https://arb-mainnet.g.alchemy.com/v2/docs-demo"

payload = {
    "jsonrpc": "2.0",
    "id": 1,
    "method": "arbtrace_replayBlockTransactions",
    "params": ["0x152DD07", ["trace"]]
}
headers = {"Content-Type": "application/json"}

response = requests.post(url, json=payload, headers=headers)

print(response.text)
```

### Go

```go
package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://arb-mainnet.g.alchemy.com/v2/docs-demo"

	payload := strings.NewReader("{\n  \"jsonrpc\": \"2.0\",\n  \"id\": 1,\n  \"method\": \"arbtrace_replayBlockTransactions\",\n  \"params\": [\n    \"0x152DD07\",\n    [\n      \"trace\"\n    ]\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}
```

### Java

```java
HttpResponse<String> response = Unirest.post("https://arb-mainnet.g.alchemy.com/v2/docs-demo")
  .header("Content-Type", "application/json")
  .body("{\n  \"jsonrpc\": \"2.0\",\n  \"id\": 1,\n  \"method\": \"arbtrace_replayBlockTransactions\",\n  \"params\": [\n    \"0x152DD07\",\n    [\n      \"trace\"\n    ]\n  ]\n}")
  .asString();
```

### C#

```csharp
using RestSharp;


var options = new RestClientOptions("https://arb-mainnet.g.alchemy.com/v2/docs-demo");
var client = new RestClient(options);
var request = new RestRequest("");
request.AddJsonBody("{\n  \"jsonrpc\": \"2.0\",\n  \"id\": 1,\n  \"method\": \"arbtrace_replayBlockTransactions\",\n  \"params\": [\n    \"0x152DD07\",\n    [\n      \"trace\"\n    ]\n  ]\n}", false);
var response = await client.PostAsync(request);

Console.WriteLine("{0}", response.Content);

```


## OpenRPC Method Specification

```yaml
name: arbtrace_replayBlockTransactions
summary: Replays all transactions in a block returning requested traces.
description: |
  Replays all transactions in the specified block and returns the requested trace types for each transaction. This is an Arbitrum-specific tracing method that works for pre-Nitro blocks (before block 22,207,815). For post-Nitro blocks, use Geth debug_* methods.
x-compute-units: 80
params:
  - name: Block number
    required: true
    description: |
      The block number as a hexadecimal string, or a block tag such as "latest", "earliest", or "pending".
    schema:
      title: Block number or tag
      oneOf:
        - title: Block number
          type: string
          pattern: ^0x([1-9a-f]+[0-9a-f]*|0)$
        - title: Block tag
          type: string
          enum:
            - earliest
            - finalized
            - safe
            - latest
            - pending
          description: '`earliest`: The lowest numbered block the client has available; `finalized`: The most recent crypto-economically secure block, cannot be re-orged outside of manual intervention driven by community coordination; `safe`: The most recent block that is safe from re-orgs under honest majority and certain synchronicity assumptions; `latest`: The most recent block in the canonical chain observed by the client, this block may be re-orged out of the canonical chain even under healthy/normal conditions; `pending`: A sample next block built by the client on top of `latest` and containing the set of transactions usually taken from local mempool. Before the merge transition is finalized, any call querying for `finalized` or `safe` block MUST be responded to with `-39001: Unknown block` error'
  - name: Trace types
    required: true
    description: |
      Array of trace types to return. Valid values: "trace", "vmTrace", "stateDiff".
    schema:
      title: Trace types
      type: array
      description: Array of trace types to return (e.g., ["trace"]).
      items:
        type: string
        enum:
          - trace
          - vmTrace
          - stateDiff
result:
  name: Block transaction traces
  description: An array of trace results, one per transaction in the block.
  schema:
    type: array
    items:
      title: Trace call result
      type: object
      properties:
        output:
          title: Output
          type: string
          description: The return value of the call, encoded as hexadecimal.
        stateDiff:
          title: State diff
          description: The state differences, if requested. Null if not requested.
          nullable: true
        trace:
          title: Trace array
          type: array
          description: Array of trace objects for the call.
          items:
            type: object
            properties:
              action:
                title: Trace action
                type: object
                properties:
                  callType:
                    title: Call type
                    type: string
                    description: The type of call (e.g., "call", "delegatecall", "staticcall").
                  from:
                    title: From address
                    type: string
                    pattern: ^0x[0-9a-fA-F]{40}$
                    description: The address of the sender.
                  gas:
                    title: Gas
                    type: string
                    pattern: ^0x([1-9a-f]+[0-9a-f]*|0)$
                    description: The gas provided for the call, encoded as hexadecimal.
                  input:
                    title: Input data
                    type: string
                    description: The input data sent with the call.
                  to:
                    title: To address
                    description: The address of the receiver. Null for contract creation.
                    oneOf:
                      - title: hex encoded address
                        type: string
                        pattern: ^0x[0-9a-fA-F]{40}$
                      - type: 'null'
                  value:
                    title: Value
                    type: string
                    pattern: ^0x([1-9a-f]+[0-9a-f]*|0)$
                    description: The value transferred in wei, encoded as hexadecimal.
              error:
                title: Error
                type: string
                nullable: true
              result:
                title: Trace result
                type: object
                properties:
                  gasUsed:
                    title: Gas used
                    type: string
                    pattern: ^0x([1-9a-f]+[0-9a-f]*|0)$
                    description: The amount of gas used by the trace, encoded as hexadecimal.
                  output:
                    title: Output
                    type: string
                    description: The return data from the call, encoded as hexadecimal.
              subtraces:
                type: integer
              traceAddress:
                type: array
                items:
                  type: integer
              type:
                type: string
        vmTrace:
          title: VM trace
          description: The VM trace, if requested. Null if not requested.
          nullable: true
examples:
  - name: arbtrace_replayBlockTransactions example
    params:
      - name: Block number
        value: '0x152DD07'
      - name: Trace types
        value:
          - trace
    result:
      name: Block transaction traces
      value:
        - output: 0x
          stateDiff: null
          trace:
            - action:
                callType: call
                from: '0x00000000000000000000000000000000000a4b05'
                gas: '0x0'
                input: 0x
                to: '0xa4b05fffffffffffffffffffffffffffffffffff'
                value: '0x0'
              result:
                gasUsed: '0x0'
                output: 0x
              subtraces: 0
              traceAddress: []
              type: call
          vmTrace: null
```