eth_simulateV1

Simulates one or more transaction bundles against the state of a given block, without broadcasting anything.

This method supports state overrides, block overrides, multi-block simulation and optional transfer tracing.

This method will use 40 Compute Units.

---

Parameters:

params - array containing:

1. simulationPayload - object - required

Configuration object for the simulation.

simulationPayload fields:

• blockStateCalls - array - required Array of block simulation objects. Each represents a simulated block.

• traceTransfers - boolean - optional If true, value transfers are included as logs. Defaults to false.

• validation - boolean - optional If true, applies validation checks such as nonce and balance. Defaults to false.

blockStateCalls object fields:

• calls - array List of transaction call objects to simulate

• stateOverrides - object - optional Override account state (balance, nonce, code, storage)

• blockOverrides - object - optional Override block-level fields (e.g. number, timestamp, baseFeePerGas)

call object fields:

• from - string - optional Sender address

• to - string Recipient address

• maxFeePerGas - string - optional Max fee per gas (hex)

• value - string - optional Value sent (hex)

• data - string - optional Hex-encoded calldata

1. blockParameter - string - required

Block number, hash, or tag such as "latest". Arc has no pending block, so use "latest".

Returns:

array of objects - simulated block results. Each object is a full block header for the simulated block plus a calls array.

Call result fields:

• status - string "0x1" = success, "0x0" = failure

• gasUsed - string Gas used (hex)

• returnData - string Return data (hex)

• logs - array Emitted logs (includes transfers if enabled)

• error - string Error or revert reason (if failed)

// Result (block header fields other than number, hash, gasUsed and baseFeePerGas omitted)
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": [
    {
      "number": "0x142bdbb",
      "hash": "0xbf966fe899c75ada50c5c73d67b18201b6c0d2c2c62e65adcb085aa928d0f8e6",
      "gasUsed": "0x5dba",
      "baseFeePerGas": "0x0",
      "calls": [
        {
          "returnData": "0x0000000000000000000000000000000000000000000000000000000000000000",
          "logs": [],
          "gasUsed": "0x5dba",
          "status": "0x1"
        }
      ]
    }
  ]
}

Example Request

mainnet

curl https://mainnet.arc.validationcloud.io/v1/<YOUR_API_KEY_HERE> \
    -X POST \
    -H "Content-Type: application/json" \
    -d '{
  "jsonrpc": "2.0",
  "method": "eth_simulateV1",
  "params": [
    {
      "blockStateCalls": [
        {
          "calls": [
            {
              "from": "0x29c7dbf15e5d385f936076736a0005433efaabf6",
              "to": "0xb329284a02508a4d09bedfdcedd4fc4ec55f3701",
              "data": "0x70a0823100000000000000000000000029c7dbf15e5d385f936076736a0005433efaabf6"
            }
          ]
        }
      ],
      "traceTransfers": false,
      "validation": false
    },
    "latest"
  ],
  "id": 1
}'

testnet

curl https://testnet.arc.validationcloud.io/v1/<YOUR_API_KEY_HERE> \
    -X POST \
    -H "Content-Type: application/json" \
    -d '{
  "jsonrpc": "2.0",
  "method": "eth_simulateV1",
  "params": [
    {
      "blockStateCalls": [
        {
          "calls": [
            {
              "from": "0xb9a912bda07024ba3c912f8d07a77760966b6d7e",
              "to": "0x3600000000000000000000000000000000000000",
              "data": "0x70a08231000000000000000000000000b9a912bda07024ba3c912f8d07a77760966b6d7e"
            }
          ]
        }
      ],
      "traceTransfers": false,
      "validation": false
    },
    "latest"
  ],
  "id": 1
}'