alchemy_simulateExecution

POST

/:apiKey

POST

/v2/:apiKey

1 curl -X POST https://eth-mainnet.g.alchemy.com/v2/{apiKey} \
2      -H "Content-Type: application/json" \
3      -d '{
4   "jsonrpc": "2.0",
5   "method": "alchemy_simulateExecution",
6   "params": [
7     "FLAT",
8     {
9       "from": "0x0dd7eef07982749410eceaa721cdc8ff3167fc9b",
10       "to": "0x68b3465833fb72a70ecdf485e0e4c7bd8665fc45",
11       "data": "0x5ae401dc00000000000000000000000000000000000000000000000000000000634ef02f...",
12       "gas": "0x22710",
13       "gasPrice": "0x3b9aca00"
14     },
15     "latest"
16   ],
17   "id": 1
18 }'

Try it

200Successful

1 {
2   "jsonrpc": "2.0",
3   "id": "1",
4   "result": {
5     "calls": [
6       {
7         "type": "CALL",
8         "from": "0x0dd7eef07982749410eceaa721cdc8ff3167fc9b",
9         "to": "0x68b3465833fb72a70ecdf485e0e4c7bd8665fc45",
10         "value": "0x0",
11         "gas": "0x22710",
12         "gasUsed": "0x1ab62",
13         "input": "0x5ae401dc0000000000...",
14         "output": "0x000000000000000000000000000000000000000000...",
15         "decoded": {
16           "authority": "ETHERSCAN",
17           "methodName": "multicall",
18           "inputs": [
19             {
20               "name": "deadline",
21               "type": "uint256",
22               "value": "1666117679"
23             },
24             {
25               "name": "data",
26               "type": "bytes[]",
27               "value": "0x04e45aaf000000000000000000000000..."
28             }
29           ],
30           "outputs": [
31             {
32               "name": "",
33               "type": "bytes[]",
34               "value": "0x000000000000000000000000000000000000000000..."
35             }
36           ]
37         }
38       }
39     ],
40     "logs": [
41       {
42         "address": "0x6b175474e89094c44da98b954eedeac495271d0f",
43         "data": "0x0000000000000000000000000000000000000000000000001bc097e5badd8f46",
44         "topics": [
45           "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
46           "0x48da0965ab2d2cbf1c17c09cfb5cbe67ad5b1406",
47           "0xdd7eef07982749410eceaa721cdc8ff3167fc9b"
48         ],
49         "decoded": {
50           "authority": "ETHERSCAN",
51           "eventName": "Transfer",
52           "inputs": [
53             {
54               "name": "src",
55               "type": "address",
56               "value": "0x48da0965ab2d2cbf1c17c09cfb5cbe67ad5b1406",
57               "indexed": true
58             },
59             {
60               "name": "dst",
61               "type": "address",
62               "value": "0x0dd7eef07982749410eceaa721cdc8ff3167fc9b",
63               "indexed": true
64             },
65             {
66               "name": "wad",
67               "type": "uint256",
68               "value": "1999765247490887494",
69               "indexed": false
70             }
71           ]
72         }
73       }
74     ],
75     "error": "",
76     "revertReason": null
77   }
78 }

Simulates a single transaction’s execution and returns decoded traces/logs.

Path parameters

apiKeystringRequired

Request

This endpoint expects an object.

formatenumRequired

Specifies whether to return a 'NESTED' or 'FLAT' call structure.

Allowed values:

transactionobjectRequired

Transaction object to simulate.

blockTagenumRequired

The block context to use: ‘latest’, ‘safe’, ‘finalized’, or ‘earliest’.

Allowed values:

Response

The decoded execution traces and logs produced by simulating the transaction.

callslist of objects

logslist of objects

errorstring or null

If the transaction would revert, error explains the reason

revertReasonstring or null

The reason why a transaction would revert. Provides details about potential transaction failure before execution.