cosmos/tx/v1beta1/simulate

Simulate a transaction for estimating gas usage.

Parameters

tx - The processable content of the transaction.

Object Name	Required	Type	Detail
`messages`	✅	Array	A list of messages to be executed. The signers of the messages define the number and order of `auth_info`'s `signer_infos` and `signatures`. By convention, the first signer (usually the first message) is referred to as the primary signer and pays the fee for the whole transaction.
`memo`	❌	String	Any arbitrary memo to be added to the transaction
`timeout_height`	✅	String	The block height after which this transaction will not be processed by the chain
`extension_options`	❌	Array	Arbitrary options that can be added by chains when the default options are not sufficient. If any of these are present and can't be handled, the transaction will be rejected.
`non_critical_extension_options`	❌	Array	Arbitrary options that can be added by chains when the default options are not sufficient. If any of these are present and can't be handled, they will be ignored.
`fee`	✅	Object	The transaction gas amount.
`signature`	✅	Object	The signature of the transaction. Contains the client `pub_key` , `account_number`, `sequence`

auth_info - The authorization related content of the transaction, specifically signers, signer modes and fee.

Key	Required	Type	Detail
`signer_info`	✅	Object	The signing modes for the required signers. The number and order of elements must match the required signers from `tx`'s messages
`fee`	✅	Object	The fee and gas limit for the transaction. The first signer is the primary signer and the one which pays the fee.

signatures - A list of signatures

Key	Required	Type	Detail
`signatures`	✅	Array	A list of signatures that matches the length and order of `auth_info`'s `signer_info`

{
    "tx": {
        "body": {
            "messages": [{
                "@type": "/cosmos.bank.v1beta1.MsgSend",
                "from_address": "cosmos1f7nwjfrks5zpaguugerjtgp2eh6fuqd0939fe2",
                "to_address": "cosmos1u4pg3qxgr8dw8k3t2lm2xz7f2zcjyehw8neckl",
                "amount": [{
                    "denom": "uatom",
                    "amount": "50000"
                }]
            }],
            "memo": "",
            "timeout_height": "0",
            "extension_options": [],
            "non_critical_extension_options": []
        },
        "auth_info": {
            "signer_infos": [{
                "public_key": {
                    "@type": "/cosmos.crypto.secp256k1.PubKey",
                    "key": "A+WiqxAgJ/fFviFCOzozjwruYy1KseuI0j/hzkJ/z2jH"
                },
                "mode_info": {
                    "single": {
                        "mode": "SIGN_MODE_LEGACY_AMINO_JSON"
                    }
                },
                "sequence": "1"
            }],
            "fee": {
                "amount": [{
                    "denom": "uatom",
                    "amount": "2000"
                }],
                "gas_limit": "80000",
                "payer": "",
                "granter": ""
            }
        },
        "signatures": ["+GbfnijcDQV96uvIJD0Ks+68bWl4aK6QR496KeBcheUx4ZOviZlaVHRBCsLOQLKy94+VJv5Ip6SEhcUEgus5eA=="]
    }
}

Result

The transaction information.

Example

Request

curl <your-rest-endpoint>/cosmos/tx/v1beta1/simulates \
  -X POST \
  -H "accept: application/json" \
  -H "Content-Type: application/json" \
  -d '{"tx": {"body":{"messages":[{"@type":"/cosmos.bank.v1beta1.MsgSend","from_address":"cosmos1f7nwjfrks5zpaguugerjtgp2eh6fuqd0939fe2","to_address":"cosmos1u4pg3qxgr8dw8k3t2lm2xz7f2zcjyehw8neckl","amount":[{"denom":"uatom","amount":"50000"}]}],"memo":"","timeout_height":"0","extension_options":[],"non_critical_extension_options":[]},"auth_info":{"signer_infos":[{"public_key":{"@type":"/cosmos.crypto.secp256k1.PubKey","key":"A+WiqxAgJ/fFviFCOzozjwruYy1KseuI0j/hzkJ/z2jH"},"mode_info":{"single":{"mode":"SIGN_MODE_LEGACY_AMINO_JSON"}},"sequence":"1"}],"fee":{"amount":[{"denom":"uatom","amount":"2000"}],"gas_limit":"80000","payer":"","granter":""}},"signatures":["+GbfnijcDQV96uvIJD0Ks+68bWl4aK6QR496KeBcheUx4ZOviZlaVHRBCsLOQLKy94+VJv5Ip6SEhcUEgus5eA=="]}}'

Return

{
  "gas_info": {
    "gas_wanted": "0",
    "gas_used": "61548"
  },
  "result": {
    "data": "Ch4KHC9jb3Ntb3MuYmFuay52MWJldGExLk1zZ1NlbmQ=",
    "log": "[{\"events\":[{\"type\":\"coin_received\",\"attributes\":[{\"key\":\"receiver\",\"value\":\"cosmos1u4pg3qxgr8dw8k3t2lm2xz7f2zcjyehw8neckl\"},{\"key\":\"amount\",\"value\":\"50000uatom\"}]},{\"type\":\"coin_spent\",\"attributes\":[{\"key\":\"spender\",\"value\":\"cosmos1f7nwjfrks5zpaguugerjtgp2eh6fuqd0939fe2\"},{\"key\":\"amount\",\"value\":\"50000uatom\"}]},{\"type\":\"message\",\"attributes\":[{\"key\":\"action\",\"value\":\"/cosmos.bank.v1beta1.MsgSend\"},{\"key\":\"sender\",\"value\":\"cosmos1f7nwjfrks5zpaguugerjtgp2eh6fuqd0939fe2\"},{\"key\":\"module\",\"value\":\"bank\"}]},{\"type\":\"transfer\",\"attributes\":[{\"key\":\"recipient\",\"value\":\"cosmos1u4pg3qxgr8dw8k3t2lm2xz7f2zcjyehw8neckl\"},{\"key\":\"sender\",\"value\":\"cosmos1f7nwjfrks5zpaguugerjtgp2eh6fuqd0939fe2\"},{\"key\":\"amount\",\"value\":\"50000uatom\"}]}]}]",
    "events": [
      {
        "type": "message",
        "attributes": [
          {
            "key": "YWN0aW9u",
            "value": "L2Nvc21vcy5iYW5rLnYxYmV0YTEuTXNnU2VuZA==",
            "index": false
          }
        ]
      },
      {
        "type": "coin_spent",
        "attributes": [
          {
            "key": "c3BlbmRlcg==",
            "value": "Y29zbW9zMWY3bndqZnJrczV6cGFndXVnZXJqdGdwMmVoNmZ1cWQwOTM5ZmUy",
            "index": false
          },
          {
            "key": "YW1vdW50",
            "value": "NTAwMDB1YXRvbQ==",
            "index": false
          }
        ]
      },
      {
        "type": "coin_received",
        "attributes": [
          {
            "key": "cmVjZWl2ZXI=",
            "value": "Y29zbW9zMXU0cGczcXhncjhkdzhrM3QybG0yeHo3ZjJ6Y2p5ZWh3OG5lY2ts",
            "index": false
          },
          {
            "key": "YW1vdW50",
            "value": "NTAwMDB1YXRvbQ==",
            "index": false
          }
        ]
      },
      {
        "type": "transfer",
        "attributes": [
          {
            "key": "cmVjaXBpZW50",
            "value": "Y29zbW9zMXU0cGczcXhncjhkdzhrM3QybG0yeHo3ZjJ6Y2p5ZWh3OG5lY2ts",
            "index": false
          },
          {
            "key": "c2VuZGVy",
            "value": "Y29zbW9zMWY3bndqZnJrczV6cGFndXVnZXJqdGdwMmVoNmZ1cWQwOTM5ZmUy",
            "index": false
          },
          {
            "key": "YW1vdW50",
            "value": "NTAwMDB1YXRvbQ==",
            "index": false
          }
        ]
      },
      {
        "type": "message",
        "attributes": [
          {
            "key": "c2VuZGVy",
            "value": "Y29zbW9zMWY3bndqZnJrczV6cGFndXVnZXJqdGdwMmVoNmZ1cWQwOTM5ZmUy",
            "index": false
          }
        ]
      },
      {
        "type": "message",
        "attributes": [
          {
            "key": "bW9kdWxl",
            "value": "YmFuaw==",
            "index": false
          }
        ]
      }
    ]
  }
}