Calculate Transaction Mass

POST

https://kas.nownodes.io/transactions/mass

Authorizations

ApiKeyAuthApiKeyAuth

api-key string

NOWNodes API key passed in the api-key header.

Changed. The returned mass is the largest of the compute mass, the storage mass (KIP-0009) and the normalized transient mass, for both v0 and v1 transactions; previously the transient mass was not taken into account, so mass could be lower. The request accepts the v1 fields (computeBudget, covenant, gas, payload).

This function calculates and returns the mass of a transaction, which is essential for determining the minimum fee. The returned mass is the largest of the compute mass, the storage mass as defined in KIP-0009 and the normalized transient mass, for both v0 and v1 transactions.

Note: Be aware that if the transaction has a very low output amount or a high number of outputs, the mass can become significantly large.

Body

application/json

versionintegerrequired

inputsArray<SubmitTxInput>required

Show child attributes

previousOutpointSubmitTxOutpointrequired

Show child attributes

transactionIdstringrequired

indexintegerrequired

signatureScriptstringrequired

sequenceintegerrequired

sigOpCountintegerrequired

computeBudgetinteger0

Compute budget of the input (v1 transactions). For v1, sigOpCount must be 0. Ignored for v0.

outputsArray<SubmitTxOutput>required

Show child attributes

amountintegerrequired

scriptPublicKeySubmitTxScriptPublicKeyrequired

Show child attributes

versionintegerrequired

scriptPublicKeystringrequired

covenantSubmitTxCovenantBinding

Covenant binding of an output (v1 transactions).

Show child attributes

authorizingInputintegerrequired

covenantIdstringrequired

lockTimeinteger0

subnetworkIdstring

gasinteger0

Gas (v1 transactions). Forced to 0 for v0.

payloadstring

Hex-encoded transaction payload. Supported for both v0 and v1 transactions.

Response

200OK

Successful Response

422Unprocessable Entity

Validation Error

Calculate Transaction Mass

curl -X POST 'https://kas.nownodes.io/transactions/mass' \
  -H 'Content-Type: application/json' \
  -d '{
    "version": 0,
    "inputs": [
      {
        "previousOutpoint": {
          "transactionId": "string",
          "index": 0
        },
        "signatureScript": "string",
        "sequence": 0,
        "sigOpCount": 0,
        "computeBudget": 0
      }
    ],
    "outputs": [
      {
        "amount": 0,
        "scriptPublicKey": {
          "version": 0,
          "scriptPublicKey": "string"
        },
        "covenant": {
          "authorizingInput": 0,
          "covenantId": "string"
        }
      }
    ],
    "lockTime": 0,
    "subnetworkId": "string",
    "gas": 0,
    "payload": ""
  }'

const response = await fetch('https://kas.nownodes.io/transactions/mass', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
      "version": 0,
      "inputs": [
        {
          "previousOutpoint": {
            "transactionId": "string",
            "index": 0
          },
          "signatureScript": "string",
          "sequence": 0,
          "sigOpCount": 0,
          "computeBudget": 0
        }
      ],
      "outputs": [
        {
          "amount": 0,
          "scriptPublicKey": {
            "version": 0,
            "scriptPublicKey": "string"
          },
          "covenant": {
            "authorizingInput": 0,
            "covenantId": "string"
          }
        }
      ],
      "lockTime": 0,
      "subnetworkId": "string",
      "gas": 0,
      "payload": ""
    }),
});

const data = await response.json();

require 'net/http'
require 'json'

uri = URI('https://kas.nownodes.io/transactions/mass')
request = Net::HTTP::Post.new(uri)
request['Content-Type'] = 'application/json'
request.body = '{
    "version": 0,
    "inputs": [
      {
        "previousOutpoint": {
          "transactionId": "string",
          "index": 0
        },
        "signatureScript": "string",
        "sequence": 0,
        "sigOpCount": 0,
        "computeBudget": 0
      }
    ],
    "outputs": [
      {
        "amount": 0,
        "scriptPublicKey": {
          "version": 0,
          "scriptPublicKey": "string"
        },
        "covenant": {
          "authorizingInput": 0,
          "covenantId": "string"
        }
      }
    ],
    "lockTime": 0,
    "subnetworkId": "string",
    "gas": 0,
    "payload": ""
  }'

response = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |http| http.request(request) }
data = JSON.parse(response.body)

import requests

payload = {
  "version": 0,
  "inputs": [
    {
      "previousOutpoint": {
        "transactionId": "string",
        "index": 0
      },
      "signatureScript": "string",
      "sequence": 0,
      "sigOpCount": 0,
      "computeBudget": 0
    }
  ],
  "outputs": [
    {
      "amount": 0,
      "scriptPublicKey": {
        "version": 0,
        "scriptPublicKey": "string"
      },
      "covenant": {
        "authorizingInput": 0,
        "covenantId": "string"
      }
    }
  ],
  "lockTime": 0,
  "subnetworkId": "string",
  "gas": 0,
  "payload": ""
}

response = requests.post('https://kas.nownodes.io/transactions/mass', json=payload)
data = response.json()

const response = await fetch('https://kas.nownodes.io/transactions/mass', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
      "version": 0,
      "inputs": [
        {
          "previousOutpoint": {
            "transactionId": "string",
            "index": 0
          },
          "signatureScript": "string",
          "sequence": 0,
          "sigOpCount": 0,
          "computeBudget": 0
        }
      ],
      "outputs": [
        {
          "amount": 0,
          "scriptPublicKey": {
            "version": 0,
            "scriptPublicKey": "string"
          },
          "covenant": {
            "authorizingInput": 0,
            "covenantId": "string"
          }
        }
      ],
      "lockTime": 0,
      "subnetworkId": "string",
      "gas": 0,
      "payload": ""
    }),
});

const data = await response.json();

const endpoint = "https://kas.nownodes.io/transactions/mass";
const apiKey = "YOUR_API_KEY";

async function nownodesRequest(payload) {
  const response = await fetch(endpoint, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      "api-key": apiKey,
    },
    body: JSON.stringify(payload),
  });

  return response.json();
}

const result = await nownodesRequest({
    "version": 0,
    "inputs": [
      {
        "previousOutpoint": {
          "transactionId": "string",
          "index": 0
        },
        "signatureScript": "string",
        "sequence": 0,
        "sigOpCount": 0,
        "computeBudget": 0
      }
    ],
    "outputs": [
      {
        "amount": 0,
        "scriptPublicKey": {
          "version": 0,
          "scriptPublicKey": "string"
        },
        "covenant": {
          "authorizingInput": 0,
          "covenantId": "string"
        }
      }
    ],
    "lockTime": 0,
    "subnetworkId": "string",
    "gas": 0,
    "payload": ""
  });
console.log(result);

const response = await fetch('https://kas.nownodes.io/transactions/mass', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
      "version": 0,
      "inputs": [
        {
          "previousOutpoint": {
            "transactionId": "string",
            "index": 0
          },
          "signatureScript": "string",
          "sequence": 0,
          "sigOpCount": 0,
          "computeBudget": 0
        }
      ],
      "outputs": [
        {
          "amount": 0,
          "scriptPublicKey": {
            "version": 0,
            "scriptPublicKey": "string"
          },
          "covenant": {
            "authorizingInput": 0,
            "covenantId": "string"
          }
        }
      ],
      "lockTime": 0,
      "subnetworkId": "string",
      "gas": 0,
      "payload": ""
    }),
});

const data = await response.json();

import requests

payload = {
  "version": 0,
  "inputs": [
    {
      "previousOutpoint": {
        "transactionId": "string",
        "index": 0
      },
      "signatureScript": "string",
      "sequence": 0,
      "sigOpCount": 0,
      "computeBudget": 0
    }
  ],
  "outputs": [
    {
      "amount": 0,
      "scriptPublicKey": {
        "version": 0,
        "scriptPublicKey": "string"
      },
      "covenant": {
        "authorizingInput": 0,
        "covenantId": "string"
      }
    }
  ],
  "lockTime": 0,
  "subnetworkId": "string",
  "gas": 0,
  "payload": ""
}

response = requests.post('https://kas.nownodes.io/transactions/mass', json=payload)
data = response.json()

require 'net/http'
require 'json'

uri = URI('https://kas.nownodes.io/transactions/mass')
request = Net::HTTP::Post.new(uri)
request['Content-Type'] = 'application/json'
request.body = '{
    "version": 0,
    "inputs": [
      {
        "previousOutpoint": {
          "transactionId": "string",
          "index": 0
        },
        "signatureScript": "string",
        "sequence": 0,
        "sigOpCount": 0,
        "computeBudget": 0
      }
    ],
    "outputs": [
      {
        "amount": 0,
        "scriptPublicKey": {
          "version": 0,
          "scriptPublicKey": "string"
        },
        "covenant": {
          "authorizingInput": 0,
          "covenantId": "string"
        }
      }
    ],
    "lockTime": 0,
    "subnetworkId": "string",
    "gas": 0,
    "payload": ""
  }'

response = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |http| http.request(request) }
data = JSON.parse(response.body)

Request Body

{
  "version": 0,
  "inputs": [
    {
      "previousOutpoint": {
        "transactionId": "string",
        "index": 0
      },
      "signatureScript": "string",
      "sequence": 0,
      "sigOpCount": 0,
      "computeBudget": 0
    }
  ],
  "outputs": [
    {
      "amount": 0,
      "scriptPublicKey": {
        "version": 0,
        "scriptPublicKey": "string"
      },
      "covenant": {
        "authorizingInput": 0,
        "covenantId": "string"
      }
    }
  ],
  "lockTime": 0,
  "subnetworkId": "string",
  "gas": 0,
  "payload": ""
}

{
  "mass": 0,
  "storage_mass": 0,
  "compute_mass": 0
}

{
  "detail": [
    {
      "loc": [
        "string"
      ],
      "msg": "string",
      "type": "string"
    }
  ]
}