simulateTransaction Solana RPC Method

POST

simulateTransaction

curl --request POST \
  --url 'https://mainnet.helius-rpc.com/?api-key=' \
  --header 'Content-Type: application/json' \
  --data '
{
  "jsonrpc": "2.0",
  "id": "1",
  "method": "simulateTransaction",
  "params": [
    "AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAABAAEDArczbMia1tLmq7zz4DinMNN0pJ1JtLdqIJPUw3YrGCzYAMHBsgN27lcgB6H2WQvFgyZuJYHa46puOQo9yQ8CVQbd9uHXZaGT2cvhRs7reawctIXtX1s3kTqM9YV+/wCp20C7Wj2aiuk5TReAXo+VTVg8QTHjs0UjNMMKCvpzZ+ABAgEBARU=",
    {
      "encoding": "base64"
    }
  ]
}
'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "context": {
      "apiVersion": "2.3.3",
      "slot": 393226680
    },
    "value": {
      "accounts": null,
      "err": null,
      "innerInstructions": null,
      "loadedAccountsDataSize": 413,
      "logs": [
        "Program TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb invoke [1]",
        "Program log: Instruction: Transfer",
        "Program TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb consumed 1714 of 200000 compute units",
        "Program TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb success"
      ],
      "replacementBlockhash": {
        "blockhash": "6oFLsE7kmgJx9PjR4R63VRNtpAVJ648gCTr3nq5Hihit",
        "lastValidBlockHeight": 381186895
      },
      "returnData": null,
      "unitsConsumed": 1714
    }
  }
}

Authorizations

api-key

string

query

required

Your Helius API key. You can get one for free in the dashboard.

Body

application/json

jsonrpc

enum<string>

default:2.0

The JSON-RPC protocol version.

Available options:

2.0

Example:

"2.0"

string

default:1

A unique identifier for the request.

Example:

"1"

method

enum<string>

default:simulateTransaction

The name of the RPC method to invoke.

Available options:

simulateTransaction

Example:

"simulateTransaction"

params

(string | object)[]

Parameters for simulating a transaction.

The signed transaction, as an encoded string (base58 or base64).

Example:

"AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAABAAEDArczbMia1tLmq7zz4DinMNN0pJ1JtLdqIJPUw3YrGCzYAMHBsgN27lcgB6H2WQvFgyZuJYHa46puOQo9yQ8CVQbd9uHXZaGT2cvhRs7reawctIXtX1s3kTqM9YV+/wCp20C7Wj2aiuk5TReAXo+VTVg8QTHjs0UjNMMKCvpzZ+ABAgEBARU="

Response

Successfully simulated the transaction.

jsonrpc

enum<string>

The JSON-RPC protocol version.

Available options:

2.0

Example:

"2.0"

string

Identifier matching the request.

Example:

"1"

result

object

Result of the simulated transaction.

Show child attributes

result.context

object

Context of the simulation response.

Show child attributes

result.context.apiVersion

string

The API version of the RPC node.

Example:

"2.3.3"

result.context.slot

integer

Slot in which the data was fetched.

Example:

393226680

result.value

object

Details of the simulated transaction result.

Show child attributes

result.value.accounts

object[] | null

result.value.err

object

Error if the transaction failed, null if successful.

Example:

null

result.value.innerInstructions

array | null

Inner instructions executed during the transaction.

Example:

null

result.value.loadedAccountsDataSize

integer | null

Total size in bytes of all account data loaded during simulation.

Example:

413

result.value.logs

string[] | null

Program execution logs from the transaction simulation.

Example:

[
  "Program TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb invoke [1]",
  "Program log: Instruction: Transfer",
  "Program TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb consumed 1714 of 200000 compute units",
  "Program TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb success"
]

result.value.replacementBlockhash

object

Replacement blockhash information when replaceRecentBlockhash is enabled.

Show child attributes

result.value.replacementBlockhash.blockhash

string

The replacement blockhash.

Example:

"6oFLsE7kmgJx9PjR4R63VRNtpAVJ648gCTr3nq5Hihit"

result.value.replacementBlockhash.lastValidBlockHeight

integer

The last valid block height for the replacement blockhash.

Example:

381186895

result.value.returnData

object

Data returned by the transaction if any.

Show child attributes

result.value.returnData.programId

string

Example:

"83astBRguLMdt2h5U1Tpdq5tjFoJ6noeGwaY3mDLVcri"

result.value.returnData.data

string[]

Example:

["Kg==", "base64"]

Example:

null

result.value.unitsConsumed

integer | null

Total compute units consumed during the simulation.

Example:

1714

OverviewThis page provides an overview of all available websocket methods that can be used to interact with the API.

⌘I

simulateTransaction

curl --request POST \
  --url 'https://mainnet.helius-rpc.com/?api-key=' \
  --header 'Content-Type: application/json' \
  --data '
{
  "jsonrpc": "2.0",
  "id": "1",
  "method": "simulateTransaction",
  "params": [
    "AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAABAAEDArczbMia1tLmq7zz4DinMNN0pJ1JtLdqIJPUw3YrGCzYAMHBsgN27lcgB6H2WQvFgyZuJYHa46puOQo9yQ8CVQbd9uHXZaGT2cvhRs7reawctIXtX1s3kTqM9YV+/wCp20C7Wj2aiuk5TReAXo+VTVg8QTHjs0UjNMMKCvpzZ+ABAgEBARU=",
    {
      "encoding": "base64"
    }
  ]
}
'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "context": {
      "apiVersion": "2.3.3",
      "slot": 393226680
    },
    "value": {
      "accounts": null,
      "err": null,
      "innerInstructions": null,
      "loadedAccountsDataSize": 413,
      "logs": [
        "Program TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb invoke [1]",
        "Program log: Instruction: Transfer",
        "Program TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb consumed 1714 of 200000 compute units",
        "Program TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb success"
      ],
      "replacementBlockhash": {
        "blockhash": "6oFLsE7kmgJx9PjR4R63VRNtpAVJ648gCTr3nq5Hihit",
        "lastValidBlockHeight": 381186895
      },
      "returnData": null,
      "unitsConsumed": 1714
    }
  }
}

API Reference

Solana RPC APIs

Solana APIs

Data Streaming APIs

Event Listening APIs

Deprecated APIs

simulateTransaction

Authorizations

Body

Response