Asset Changes

Simulates a transaction and returns a list of asset changes.

📘
Try it out - alchemy_simulateAssetChanges.

How does it work?

You give us a transaction (unsigned transaction object) 📦
We simulate your transaction on our blazing fast infra ⚡
We return a complete list of asset changes (including tokens and NFTs) 💸

What do you get back?

We currently return the following info:

gas used
change type (approval, transfer)
asset type (native, erc20, erc721, erc1155, special nft)
sender / destination
amount
additional metadata (logo, token id, contract address)

Examples

👍
Chain support
The examples below are for Eth Mainnet and Polygon Mainnet.
Simulation also works on Arbitrum and testnets - more examples coming soon!

Ethereum

ETH - Transfer

0xbe0eb53f46cd790cd13851d5eff43d12404d33e8 sending 1 ETH to 0xc02aaa39b223fe8d050e5c4f27ead9083c756cc2.

To send a normal transfer, remove the data field from the transaction object in the request.
We will add support for data: " " and data: "0x" soon.

{
  "from": "0xBE0eB53F46cd790Cd13851d5EFf43D12404d33E8",
  "to": "0xc02aaa39b223fe8d050e5c4f27ead9083c756cc2",
  "value": "0xDE0B6B3A7640000"
}

curl --location --request POST 'https://eth-mainnet.g.alchemy.com/v2/YOUR_KEY' \
--header 'Content-Type: application/json' \
--data-raw '{
  "jsonrpc": "2.0",
  "method": "alchemy_simulateAssetChanges",
  "id": 1,
  "params": [
    {
      "from": "0xBE0eB53F46cd790Cd13851d5EFf43D12404d33E8",
      "to": "0xc02aaa39b223fe8d050e5c4f27ead9083c756cc2",
      "value": "0xDE0B6B3A7640000"
    }
  ]
}'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "changes": [
      {
        "assetType": "NATIVE",
        "changeType": "TRANSFER",
        "from": "0xbe0eb53f46cd790cd13851d5eff43d12404d33e8",
        "to": "0xc02aaa39b223fe8d050e5c4f27ead9083c756cc2",
        "rawAmount": "1000000000000000000",
        "contractAddress": null,
        "tokenId": null,
        "decimals": 18,
        "symbol": "ETH",
        "name": "Ethereum",
        "logo": "https://static.alchemyapi.io/images/network-assets/eth.png",
        "amount": "1"
      }
    ],
    "gasUsed": "0x0",
    "error": null
  }
}

// npm install alchemy-sdk
import { Network, Alchemy } from "alchemy-sdk";

const alchemy = new Alchemy({
  apiKey: "demo", // Replace with your Alchemy API Key.
  network: Network.ETH_MAINNET,
});

(async => {
  const transaction = {
  	from: "0xBE0eB53F46cd790Cd13851d5EFf43D12404d33E8",
  	to: "0xc02aaa39b223fe8d050e5c4f27ead9083c756cc2",
  	value: "0xDE0B6B3A7640000"
	};
  const { changes, error } = await alchemy.transact.simulateAssetChanges(transaction);
  console.log('Changes', changes);
  console.log('Error', error);
})();

ERC20 - Transfer

vitalik.eth (0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045) sending 1 USDC to demo.eth (0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48).

{
   "from": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
   "to": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
   "value": "0x0",
   "data": "0xa9059cbb000000000000000000000000fc43f5f9dd45258b3aff31bdbe6561d97e8b71de00000000000000000000000000000000000000000000000000000000000f4240"
 }

curl --location --request POST 'https://eth-mainnet.g.alchemy.com/v2/YOUR_KEY' \
--header 'Content-Type: application/json' \
--data-raw '{
  "jsonrpc": "2.0",
  "method": "alchemy_simulateAssetChanges",
  "id": 1,
  "params": [
    {
      "from": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
      "to": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
      "value": "0x0",
      "data": "0xa9059cbb000000000000000000000000fc43f5f9dd45258b3aff31bdbe6561d97e8b71de00000000000000000000000000000000000000000000000000000000000f4240"
    }
  ]
}'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "changes": [
      {
        "assetType": "ERC20",
        "changeType": "TRANSFER",
        "from": "0xd8da6bf26964af9d7eed9e03e53415d37aa96045",
        "to": "0xfc43f5f9dd45258b3aff31bdbe6561d97e8b71de",
        "rawAmount": "1000000",
        "contractAddress": "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48",
        "tokenId": null,
        "decimals": 6,
        "symbol": "USDC",
        "name": "USD Coin",
        "logo": "https://static.alchemyapi.io/images/assets/3408.png",
        "amount": "1"
      }
    ],
    "gasUsed": "0x6925",
    "error": null
  }
}

// npm install alchemy-sdk
import { Network, Alchemy } from "alchemy-sdk";

const alchemy = new Alchemy({
  apiKey: "demo", // Replace with your Alchemy API Key.
  network: Network.ETH_MAINNET,
});

(async => {
  const transaction = {
  	from: "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
  	to: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
   	value: "0x0",
   	data: "0xa9059cbb000000000000000000000000fc43f5f9dd45258b3aff31bdbe6561d97e8b71de00000000000000000000000000000000000000000000000000000000000f4240"
	};
  const { changes, error } = await alchemy.transact.simulateAssetChanges(transaction);
  console.log('Changes', changes);
  console.log('Error', error);
})();

WETH - Wrap

0xBE0eB53F46cd790Cd13851d5EFf43D12404d33E8 depositing 1 ETH and getting 1 WETH back.

{
  "from": "0xBE0eB53F46cd790Cd13851d5EFf43D12404d33E8",
  "to": "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
  "data": "0xd0e30db0",
  "value": "0xDE0B6B3A7640000"
}

curl --location --request POST 'https://eth-mainnet.g.alchemy.com/v2/YOUR_KEY' \
--header 'Content-Type: application/json' \
--data-raw '{
  "jsonrpc": "2.0",
  "method": "alchemy_simulateAssetChanges",
  "id": 1,
  "params": [
    {
      "from": "0xBE0eB53F46cd790Cd13851d5EFf43D12404d33E8",
      "to": "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
      "data": "0xd0e30db0",
      "value": "0xDE0B6B3A7640000"
    }
  ]
}'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "changes": [
      {
        "assetType": "NATIVE",
        "changeType": "TRANSFER",
        "from": "0xbe0eb53f46cd790cd13851d5eff43d12404d33e8",
        "to": "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
        "rawAmount": "1000000000000000000",
        "contractAddress": null,
        "tokenId": null,
        "decimals": 18,
        "symbol": "ETH",
        "name": "Ethereum",
        "logo": "https://static.alchemyapi.io/images/network-assets/eth.png",
        "amount": "1"
      },
      {
        "assetType": "ERC20",
        "changeType": "TRANSFER",
        "from": "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
        "to": "0xbe0eb53f46cd790cd13851d5eff43d12404d33e8",
        "rawAmount": "1000000000000000000",
        "contractAddress": "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
        "tokenId": null,
        "decimals": 18,
        "symbol": "WETH",
        "name": "WETH",
        "logo": "https://static.alchemyapi.io/images/assets/2396.png",
        "amount": "1"
      }
    ],
    "gasUsed": "0x5da6",
    "error": null
  }
}

// npm install alchemy-sdk
import { Network, Alchemy } from "alchemy-sdk";

const alchemy = new Alchemy({
  apiKey: "demo", // Replace with your Alchemy API Key.
  network: Network.ETH_MAINNET,
});

(async => {
  const transaction = {
    from: "0xBE0eB53F46cd790Cd13851d5EFf43D12404d33E8",
    to: "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
    data: "0xd0e30db0",
    value: "0xDE0B6B3A7640000"
  };
  const { changes, error } = await alchemy.transact.simulateAssetChanges(transaction);
  console.log('Changes', changes);
  console.log('Error', error);
})();

WETH - Unwrap

0x2e95E1cD077f29733C65D885Ce7AFE278d0726A6 withdrawing 1 ETH (1 WETH sent, 1 ETH returned).

{
  "from": "0x2e95E1cD077f29733C65D885Ce7AFE278d0726A6",
  "to": "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
  "value": "0x0",
  "data": "0x2e1a7d4d0000000000000000000000000000000000000000000000000de0b6b3a7640000"
}

curl --location --request POST 'https://eth-mainnet.g.alchemy.com/v2/YOUR_KEY' \
--header 'Content-Type: application/json' \
--data-raw '{
  "jsonrpc": "2.0",
  "method": "alchemy_simulateAssetChanges",
  "id": 1,
  "params": [
    {
      "from": "0x2e95E1cD077f29733C65D885Ce7AFE278d0726A6",
      "to": "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
      "value": "0x0",
      "data": "0x2e1a7d4d0000000000000000000000000000000000000000000000000de0b6b3a7640000"
    }
  ]
}'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "changes": [
      {
        "assetType": "NATIVE",
        "changeType": "TRANSFER",
        "from": "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
        "to": "0x2e95e1cd077f29733c65d885ce7afe278d0726a6",
        "rawAmount": "1000000000000000000",
        "contractAddress": null,
        "tokenId": null,
        "decimals": 18,
        "symbol": "ETH",
        "name": "Ethereum",
        "logo": "https://static.alchemyapi.io/images/network-assets/eth.png",
        "amount": "1"
      },
      {
        "assetType": "ERC20",
        "changeType": "TRANSFER",
        "from": "0x2e95e1cd077f29733c65d885ce7afe278d0726a6",
        "to": "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
        "rawAmount": "1000000000000000000",
        "contractAddress": "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
        "tokenId": null,
        "decimals": 18,
        "symbol": "WETH",
        "name": "WETH",
        "logo": "https://static.alchemyapi.io/images/assets/2396.png",
        "amount": "1"
      }
    ],
    "gasUsed": "0x3674",
    "error": null
  }
}

// npm install alchemy-sdk
import { Network, Alchemy } from "alchemy-sdk";

const alchemy = new Alchemy({
  apiKey: "demo", // Replace with your Alchemy API Key.
  network: Network.ETH_MAINNET,
});

(async => {
  const transaction = {
  	from: "0x2e95E1cD077f29733C65D885Ce7AFE278d0726A6",
  	to: "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
  	value: "0x0",
  	data: "0x2e1a7d4d0000000000000000000000000000000000000000000000000de0b6b3a7640000"
	};
  const { changes, error } = await alchemy.transact.simulateAssetChanges(transaction);
  console.log('Changes', changes);
  console.log('Error', error);
})();

Polygon

MATIC - Transfer

0xe7804c37c13166ff0b37f5ae0bb07a3aebb6e245 sending 5 MATIC to 0x0d500b1d8e8ef31e21c99e1db9a6444d3adf1270.

To send a normal transfer, remove the data field from the transaction object in the request.
We will add support for data: " " and data: "0x" soon.

{
  "from": "0xe7804c37c13166fF0b37F5aE0BB07A3aEbb6e245",
  "to": "0x0d500b1d8e8ef31e21c99e1db9a6444d3adf1270",
  "value": "0x4563918244F40000"
}

curl --location --request POST 'https://polygon-mainnet.g.alchemy.com/v2/YOUR_KEY' \
--header 'Content-Type: application/json' \
--data-raw '{
  "jsonrpc": "2.0",
  "method": "alchemy_simulateAssetChanges",
  "id": 1,
  "params": [
    {
      "from": "0xe7804c37c13166fF0b37F5aE0BB07A3aEbb6e245",
      "to": "0x0d500b1d8e8ef31e21c99e1db9a6444d3adf1270",
      "value": "0x4563918244F40000"
    }
  ]
}'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "changes": [
      {
        "assetType": "NATIVE",
        "changeType": "TRANSFER",
        "from": "0xe7804c37c13166ff0b37f5ae0bb07a3aebb6e245",
        "to": "0x0d500b1d8e8ef31e21c99e1db9a6444d3adf1270",
        "rawAmount": "5000000000000000000",
        "contractAddress": null,
        "tokenId": null,
        "decimals": 18,
        "symbol": "MATIC",
        "name": "MATIC",
        "logo": "https://static.alchemyapi.io/images/network-assets/matic.png",
        "amount": "5"
      }
    ],
    "gasUsed": "0x0",
    "error": null
  }
}

// npm install alchemy-sdk
import { Network, Alchemy } from "alchemy-sdk";

const alchemy = new Alchemy(settings);
const alchemy = new Alchemy({
  apiKey: "demo", // Replace with your Alchemy API Key.
  network: Network.MATIC_MAINNET,
});

(async => {
  const transaction = {
  	from: "0xe7804c37c13166fF0b37F5aE0BB07A3aEbb6e245",
    to: "0x0d500b1d8e8ef31e21c99e1db9a6444d3adf1270",
    value: "0x4563918244F40000"
  };
  const { changes, error } = await alchemy.transact.simulateAssetChanges(transaction);
  console.log('Changes', changes);
  console.log('Error', error);
})();

ERC20 - Transfer

0xf977814e90da44bfa03b6295a0616a897441acec sending 1 USDC to 0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174.

{
  "from": "0xF977814e90dA44bFA03b6295A0616a897441aceC",
  "to": "0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174",
  "value": "0x0",
  "data": "0xa9059cbb000000000000000000000000fc43f5f9dd45258b3aff31bdbe6561d97e8b71de00000000000000000000000000000000000000000000000000000000000f4240"
}

curl --location --request POST 'https://polygon-mainnet.g.alchemy.com/v2/YOUR_KEY' \
--header 'Content-Type: application/json' \
--data-raw '{
  "jsonrpc": "2.0",
  "method": "alchemy_simulateAssetChanges",
  "id": 1,
  "params": [
    {
      "from": "0xF977814e90dA44bFA03b6295A0616a897441aceC",
      "to": "0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174",
      "value": "0x0",
      "data": "0xa9059cbb000000000000000000000000fc43f5f9dd45258b3aff31bdbe6561d97e8b71de00000000000000000000000000000000000000000000000000000000000f4240"
    }
  ]
}'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "changes": [
      {
        "assetType": "ERC20",
        "changeType": "TRANSFER",
        "from": "0xf977814e90da44bfa03b6295a0616a897441acec",
        "to": "0xfc43f5f9dd45258b3aff31bdbe6561d97e8b71de",
        "rawAmount": "1000000",
        "contractAddress": "0x2791bca1f2de4661ed88a30c99a7a9449aa84174",
        "tokenId": null,
        "decimals": 6,
        "symbol": "USDC",
        "name": "USD Coin (PoS)",
        "logo": null,
        "amount": "1"
      }
    ],
    "gasUsed": "0xa3d8",
    "error": null
  }
}

// npm install alchemy-sdk
import { Network, Alchemy } from "alchemy-sdk";

const alchemy = new Alchemy(settings);
const alchemy = new Alchemy({
  apiKey: "demo", // Replace with your Alchemy API Key.
  network: Network.MATIC_MAINNET,
});

(async => {
  const transaction = {
    from: "0xF977814e90dA44bFA03b6295A0616a897441aceC",
    to: "0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174",
    value: "0x0",
    data: "0xa9059cbb000000000000000000000000fc43f5f9dd45258b3aff31bdbe6561d97e8b71de00000000000000000000000000000000000000000000000000000000000f4240"
  };
  const { changes, error } = await alchemy.transact.simulateAssetChanges(transaction);
  console.log('Changes', changes);
  console.log('Error', error);
})();

WMATIC - Wrap

0xe7804c37c13166fF0b37F5aE0BB07A3aEbb6e245 depositing 5 MATIC and getting 5 WMATIC back.

{
  "from": "0xe7804c37c13166fF0b37F5aE0BB07A3aEbb6e245",
  "to": "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
  "data": "0xd0e30db0",
  "value": "0x4563918244F40000"
}

curl --location --request POST 'https://polygon-mainnet.g.alchemy.com/v2/YOUR_KEY' \
--header 'Content-Type: application/json' \
--data-raw '{
  "jsonrpc": "2.0",
  "method": "alchemy_simulateAssetChanges",
  "id": 1,
  "params": [
    {
      "from": "0xe7804c37c13166fF0b37F5aE0BB07A3aEbb6e245",
      "to": "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
      "data": "0xd0e30db0",
      "value": "0x4563918244F40000"
    }
  ]
}'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "changes": [
      {
        "assetType": "NATIVE",
        "changeType": "TRANSFER",
        "from": "0xe7804c37c13166ff0b37f5ae0bb07a3aebb6e245",
        "to": "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
        "rawAmount": "5000000000000000000",
        "contractAddress": null,
        "tokenId": null,
        "decimals": 18,
        "symbol": "MATIC",
        "name": "MATIC",
        "logo": "https://static.alchemyapi.io/images/network-assets/matic.png",
        "amount": "5"
      },
      {
        "assetType": "ERC20",
        "changeType": "TRANSFER",
        "from": "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
        "to": "0xe7804c37c13166ff0b37f5ae0bb07a3aebb6e245",
        "rawAmount": "5000000000000000000",
        "contractAddress": "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
        "tokenId": null,
        "decimals": 18,
        "symbol": "WMATIC",
        "name": "Wrapped Matic",
        "logo": "https://static.alchemyapi.io/images/assets/8925.png",
        "amount": "5"
      }
    ],
    "gasUsed": "0x1add",
    "error": null
  }
}

// npm install alchemy-sdk
import { Network, Alchemy } from "alchemy-sdk";

const alchemy = new Alchemy(settings);
const alchemy = new Alchemy({
  apiKey: "demo", // Replace with your Alchemy API Key.
  network: Network.MATIC_MAINNET,
});

(async => {
  const transaction = {
  	from: "0xe7804c37c13166fF0b37F5aE0BB07A3aEbb6e245",
  	to: "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
  	data: "0xd0e30db0",
  	value: "0x4563918244F40000"
	};
  const { changes, error } = await alchemy.transact.simulateAssetChanges(transaction);
  console.log('Changes', changes);
  console.log('Error', error);
})();

WMATIC - Unwrap

0xccc52f64ee0fff73ad7312825ee767ce94d4877a withdrawing 1 MATIC (1 WMATIC sent, 1 MATIC returned).

{
  "from": "0xccc52f64ee0fff73ad7312825ee767ce94d4877a",
 	"to": "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
  "value": "0x0",
  "data": "0x2e1a7d4d0000000000000000000000000000000000000000000000000de0b6b3a7640000"
}

curl --location --request POST 'https://polygon-mainnet.g.alchemy.com/v2/YOUR_KEY' \
--header 'Content-Type: application/json' \
--data-raw '{
  "jsonrpc": "2.0",
  "method": "alchemy_simulateAssetChanges",
  "id": 1,
  "params": [
    {
      "from": "0xccc52f64ee0fff73ad7312825ee767ce94d4877a",
      "to": "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
      "value": "0x0",
      "data": "0x2e1a7d4d0000000000000000000000000000000000000000000000000de0b6b3a7640000"
    }
  ]
}'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "changes": [
      {
        "assetType": "NATIVE",
        "changeType": "TRANSFER",
        "from": "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
        "to": "0xccc52f64ee0fff73ad7312825ee767ce94d4877a",
        "rawAmount": "1000000000000000000",
        "contractAddress": null,
        "tokenId": null,
        "decimals": 18,
        "symbol": "MATIC",
        "name": "MATIC",
        "logo": "https://static.alchemyapi.io/images/network-assets/matic.png",
        "amount": "1"
      },
      {
        "assetType": "ERC20",
        "changeType": "TRANSFER",
        "from": "0xccc52f64ee0fff73ad7312825ee767ce94d4877a",
        "to": "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
        "rawAmount": "1000000000000000000",
        "contractAddress": "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
        "tokenId": null,
        "decimals": 18,
        "symbol": "WMATIC",
        "name": "Wrapped Matic",
        "logo": "https://static.alchemyapi.io/images/assets/8925.png",
        "amount": "1"
      }
    ],
    "gasUsed": "0x3697",
    "error": null
  }
}

// npm install alchemy-sdk
import { Network, Alchemy } from "alchemy-sdk";

const alchemy = new Alchemy(settings);
const alchemy = new Alchemy({
  apiKey: "demo", // Replace with your Alchemy API Key.
  network: Network.MATIC_MAINNET,
});

(async => {
  const transaction = {
    from: "0xccc52f64ee0fff73ad7312825ee767ce94d4877a",
    to: "0x0d500b1d8e8ef31e21c99d1db9a6444d3adf1270",
    value: "0x0",
    data: "0x2e1a7d4d0000000000000000000000000000000000000000000000000de0b6b3a7640000"
  };
  const { changes, error } = await alchemy.transact.simulateAssetChanges(transaction);
  console.log('Changes', changes);
  console.log('Error', error);
})();

For a deep dive check out our Asset Changes - Explained guide.

Asset Changes

📘

How does it work?

What do you get back?

Examples

👍
Chain support

Ethereum

ETH - Transfer

ERC20 - Transfer

WETH - Wrap

WETH - Unwrap

Polygon

MATIC - Transfer

ERC20 - Transfer

WMATIC - Wrap

WMATIC - Unwrap

APIs

DEVELOPERS

Company

CONTACT

📘

How does it work?

What do you get back?

Examples

👍Chain support

Ethereum

ETH - Transfer

ERC20 - Transfer

WETH - Wrap

WETH - Unwrap

Polygon

MATIC - Transfer

ERC20 - Transfer

WMATIC - Wrap

WMATIC - Unwrap

APIs

DEVELOPERS

Company

CONTACT

👍
Chain support