Include library const { getEtherBalances, getTokenBalances } = require("@mycrypto/eth-scan"); Testnet - 0x3c72F876E5C6d02315Ba6e3a39F2f10862FE98FC getEtherBalances('http://35.220.203.194:8545', [ 'address1', ... ], { contractAddress: "0x3c72F876E5C6d02315Ba6e3a39F2f10862FE98FC" }).then(console.log); getTokenBalances('http://35.220.203.194:8545', [ 'address...', ... ], '--you-token-address--', // <- put your token address here { contractAddress: "0x3c72F876E5C6d02315Ba6e3a39F2f10862FE98FC" }).then(console.log); Mainnet - 0xd2A9a1b0b2d4160610E1ec1BC51bdc8a55aDD349 getEtherBalances('https://smartbch.greyh.at', [ 'address1', ... ], { contractAddress: "0xd2A9a1b0b2d4160610E1ec1BC51bdc8a55aDD349" }).then(console.log);