Simulate JSON RPC

Custom JSON RPC method available in Tenderly Web3 Gateway.
The custom RPC methods appear in the tenderly_ namespace.
tenderly_simulateTransaction
Simulates transaction as it would execute on the given block.
PARAMS
1.Transaction Transaction OBJECT
from (optional) STRING: hex encoded address
to STRING: hex encoded address
gas (optional) NUMBER
maxFeePerGas (optional) NUMBER max fee: The maximum total fee per gas the sender is willing to pay (includes the network / base fee and miner / priority fee) in wei
maxPriorityFeePerGas (optional) NUMBER max priority fee: Maximum fee per gas the sender is willing to pay to miners in wei
gasPrice (optional) NUMBER: The gas price willing to be paid by the sender in wei
value (optional) NUMBER
data (optional) STRING: hex encoded bytes
accessList (optional) ARRAY of Access list entry OBJECT
address STRING hex encoded address
storageKeys ARRAY of STRING representation of 32 byte hex encoded storage key
2.Simulation Block Number (optional) The block number against which transaction should be simulated. Either:
STRING Block number
ENUM of Block tag earliest|finalized|safe|latest|pending
3.Overrides (optional) MAP: mapping from an account (address) to override specification
key STRING: the account this override applies to
value OBJECT: the override specification
nonce (optional) STRING: hex encoded 8 byte nonce override for the account
code (optional) STRING: data of the code override for the account
balance (optional) STRING: hex encoded 32 byte balance override for the account in wei
stateDiff (optional) MAP: mapping of storage key to storage value override
key STRING: the storage key
value STRING: the value override for the given storage key
Raw
cURL
ethers
Response
{
  "id": 0,
  "jsonrpc": "2.0",
  "method": "tenderly_simulateTransaction",
  "params": [
    {
      "from": "0xDC6bDc37B2714eE601734cf55A05625C9e512461",
      "to": "0xff39a3e734fe363e631441f6d24c7539240c2628",
      "value": "0x0",
      "data": "0x2e7700f0"
    },
    "0xF4D880",
    null
  ]
}
​
curl https://mainnet.gateway.tenderly.co/$TENDERLY_WEB3_GATEWAY_KEY \
-X POST \
-H "Content-Type: application/json" \
-d \
'{
  "id": 0,
  "jsonrpc": "2.0",
  "method": "tenderly_simulateTransaction",
  "params": [
    {
      "from": "0xDC6bDc37B2714eE601734cf55A05625C9e512461",
      "to": "0xff39a3e734fe363e631441f6d24c7539240c2628",
      "value": "0x0",
      "data": "0x2e7700f0"
    },
    "0xF4D880",
    null
  ]
}'
​
// Installation Instructions: https://docs.ethers.io/v5/getting-started/#installing
const { ethers } = require("ethers");
​
async function runSimulateTransaction() {
  // Initialize an ethers instance
  const provider = new ethers.providers.JsonRpcProvider(
    "https://goerli.gateway.tenderly.co/$TENDERLY_WEB3_GATEWAY_KEY"
  );
​
  // Execute method
  const result = await provider.send("tenderly_simulateTransaction", [
    {
      from: "0xDC6bDc37B2714eE601734cf55A05625C9e512461",
      to: "0xff39a3e734fe363e631441f6d24c7539240c2628",
      value: "0x0",
      data: "0x2e7700f0",
    },
    "0xF4D880",
  ]);
​
  // Print the output to console
  console.log(result);
}
​
(async () => {
  runSimulateTransaction();
})();
{
  "id": 0,
  "jsonrpc": "2.0",
  "result": {
    "status": true,
    "gasUsed": "0x523c",
    "cumulativeGasUsed": "0x0",
    "blockNumber": "0xf4d881",
    "type": "0x0",
    "logsBloom": "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
    "logs": null,
    "trace": [
      {
        "type": "CALL",
        "from": "0xdc6bdc37b2714ee601734cf55a05625c9e512461",
        "to": "0xff39a3e734fe363e631441f6d24c7539240c2628",
        "gas": "0x5f58ec4",
        "gasUsed": "0x0",
        "value": "0x0",
        "input": "0x2e7700f0",
        "decodedInput": null,
        "method": null,
        "output": "0x",
        "decodedOutput": null,
        "subtraces": 0,
        "traceAddress": [0]
      }
    ]
  }
}
RESULT: Simulation result OBJECT
status NUMBER: either 1 (success) or 0 (failure)
gasUsed NUMBER: The amount of gas used by this specific transaction alone
cumulativeGasUsed NUMBER: the total amount of gas used when this transaction was executed in the block
blockNumber NUMBER: the block number in which this transaction was simulated
type NUMBER: transaction type, 0x00 for legacy transactions, 0x01 for access list types, 0x02 for dynamic fees
logsBloom STRING: bloom filter for light clients to quickly retrieve related logs
logs: an array of emitted events ARRAY of OBJECT
name STRING: event name
anonymous BOOLEAN: indicates if event is anonymous
inputs: array of decoded log arguments ARRAY of decoded logs OBJECT
name STRING: event argument name
type STRING: event argument type from Solidity type system
value (optional) STRING string representation value of the argument; interpret according to the type field
raw OBJECT: raw logs
address STRING hex encoded address: address of the contract emitting the log
topics ARRAY of STRING 32 hex encoded bytes
data STRING hex encoded string representing event data
trace: Trace ARRAY of OBJECT
type STRING type: trace item type - either CALL| CALLCODE| STATICCALL| DELEGATECALL| CREATE| CREATE2| SELFDESTRUCT
from STRING: hex encoded address
to STRING: hex encoded address
gas STRING: hex encoded unsigned 64 byte integer representing event gas
gasUsed STRING: hex encoded unsigned 64 byte integer representing event gasUsed
value STRING: hex encoded unsigned 64 byte integer representing event value in wei
error STRING: low-level error from virtual machine
errorReason STRING: extracted error reason in case of revert
input STRING: hex encoded string representation of raw input bytes for the trace point
method STRING: invoked contract method
decodedInput : decoded input for the invoked method - ARRAY of decoded in argument OBJECT
value STRING: string representation value of the argument; interpret according to the type field.
type STRING: the Solidity type of this argument
name STRING: the name of this argument
output STRING: raw trace output
decodedOutput : decoded output of the invoked method - ARRAY of decoded out argument OBJECT
value STRING: string representation value of the argument; interpret according to the type field.
type STRING: the Solidity type of this argument
name STRING: the name of this argument
subtraces NUMBER: number of child traces
traceAddress : trace position ARRAY of NUMBER
​
Detailed JSON RPC reference
Simulate Bundle JSON RPC
Last modified 1mo ago