@cosmjs/amino

Provides Amino JSON encoding and signing capabilities for Cosmos SDK transactions. Essential for legacy signing, Ledger hardware wallets, and backwards compatibility.

npm install @cosmjs/amino

Secp256k1HdWallet

HD wallet using BIP-39 mnemonic with Amino JSON signing. Implements OfflineAminoSigner.

Static Methods

Method	Parameters	Returns
`generate`	`length?: 12 \| 15 \| 18 \| 21 \| 24`, `options?: Partial<Secp256k1HdWalletOptions>`	`Promise<Secp256k1HdWallet>`
`fromMnemonic`	`mnemonic: string`, `options?: Partial<Secp256k1HdWalletOptions>`	`Promise<Secp256k1HdWallet>`
`deserialize`	`serialization: string`, `password: string`	`Promise<Secp256k1HdWallet>`
`deserializeWithEncryptionKey`	`serialization: string`, `encryptionKey: Uint8Array`	`Promise<Secp256k1HdWallet>`

Instance Methods

Method	Parameters	Returns
`getAccounts`	—	`Promise<readonly AccountData[]>`
`signAmino`	`signerAddress: string`, `signDoc: StdSignDoc`	`Promise<AminoSignResponse>`
`serialize`	`password: string`	`Promise<string>`
`serializeWithEncryptionKey`	`encryptionKey: Uint8Array`, `kdfConfiguration: KdfConfiguration`	`Promise<string>`

Instance Properties

Property	Type
`mnemonic`	`string`

Options

interface Secp256k1HdWalletOptions {
  readonly bip39Password: string;      // default: ""
  readonly hdPaths: readonly HdPath[]; // default: [makeCosmoshubPath(0)]
  readonly prefix: string;             // default: "cosmos"
}

Usage

import { Secp256k1HdWallet, makeCosmoshubPath } from "@cosmjs/amino";

const wallet = await Secp256k1HdWallet.fromMnemonic("your mnemonic ...", {
  prefix: "cosmos",
  hdPaths: [makeCosmoshubPath(0), makeCosmoshubPath(1)],
});

const [account1, account2] = await wallet.getAccounts();

Secp256k1Wallet

Single-key wallet for Amino JSON signing. Implements OfflineAminoSigner.

Method	Parameters	Returns
`fromKey` (static)	`privkey: Uint8Array`, `prefix?: string`	`Promise<Secp256k1Wallet>`
`getAccounts`	—	`Promise<readonly AccountData[]>`
`signAmino`	`signerAddress: string`, `signDoc: StdSignDoc`	`Promise<AminoSignResponse>`

Address Functions

Function	Parameters	Returns
`pubkeyToAddress`	`pubkey: Pubkey`, `prefix: string`	`string`
`pubkeyToRawAddress`	`pubkey: Pubkey`	`Uint8Array`
`rawSecp256k1PubkeyToRawAddress`	`pubkeyRaw: Uint8Array`	`Uint8Array`
`rawEd25519PubkeyToRawAddress`	`pubkeyRaw: Uint8Array`	`Uint8Array`
`rawEthSecp256k1PubkeyToRawAddress`	`pubkeyRaw: Uint8Array`	`Uint8Array`

Coin Utilities

Function	Parameters	Returns
`coin`	`amount: number \| string`, `denom: string`	`Coin`
`coins`	`amount: number \| string`, `denom: string`	`Coin[]`
`parseCoins`	`input: string`	`Coin[]`
`addCoins`	`lhs: Coin`, `rhs: Coin`	`Coin`

import { coin, coins, parseCoins, addCoins } from "@cosmjs/amino";

const amount = coin(1000000, "uatom");
const amounts = coins(500, "uatom");
const parsed = parseCoins("1000uatom,500ustake");
const total = addCoins(coin(100, "uatom"), coin(50, "uatom"));

Pubkey Encoding

Function	Parameters	Returns
`encodeSecp256k1Pubkey`	`pubkey: Uint8Array`	`Secp256k1Pubkey`
`encodeEd25519Pubkey`	`pubkey: Uint8Array`	`Ed25519Pubkey`
`encodeEthSecp256k1Pubkey`	`pubkey: Uint8Array`	`EthSecp256k1Pubkey`
`encodeAminoPubkey`	`pubkey: Pubkey`	`Uint8Array`
`decodeAminoPubkey`	`amino: Uint8Array`	`Pubkey`
`encodeBech32Pubkey`	`pubkey: Pubkey`, `prefix: string`	`string`
`decodeBech32Pubkey`	`bechEncoded: string`	`Pubkey`

Signature Functions

Function	Parameters	Returns
`encodeSecp256k1Signature`	`pubkey: Uint8Array`, `signature: Uint8Array`	`StdSignature`
`encodeEthSecp256k1Signature`	`pubkey: Uint8Array`, `signature: Uint8Array`	`StdSignature`
`decodeSignature`	`signature: StdSignature`	`{ pubkey: Uint8Array; signature: Uint8Array }`

Sign Document Functions

Function	Parameters	Returns
`makeSignDoc`	`msgs: readonly AminoMsg[]`, `fee: StdFee`, `chainId: string`, `memo: string \| undefined`, `accountNumber: number \| string`, `sequence: number \| string`, `timeout_height?: bigint`	`StdSignDoc`
`serializeSignDoc`	`signDoc: StdSignDoc`	`Uint8Array`

Multisig

Function	Parameters	Returns
`createMultisigThresholdPubkey`	`pubkeys: readonly SinglePubkey[]`, `threshold: number`, `nosort?: boolean`	`MultisigThresholdPubkey`

When nosort is false (default), pubkeys are sorted by their raw address to match the Cosmos SDK client behavior. Pass true to preserve the input order.

Key Types

Coin

interface Coin {
  readonly denom: string;
  readonly amount: string;
}

StdFee

interface StdFee {
  readonly amount: readonly Coin[];
  readonly gas: string;
  readonly granter?: string;
  readonly payer?: string;
}

AminoMsg

interface AminoMsg {
  readonly type: string;
  readonly value: Record<string, any>;
}

StdSignDoc

interface StdSignDoc {
  readonly chain_id: string;
  readonly account_number: string;
  readonly sequence: string;
  readonly fee: StdFee;
  readonly msgs: readonly AminoMsg[];
  readonly memo: string;
  readonly timeout_height?: string;
}

AccountData

interface AccountData {
  readonly address: string;
  readonly algo: Algo;
  readonly pubkey: Uint8Array;
}

OfflineAminoSigner

interface OfflineAminoSigner {
  readonly getAccounts: () => Promise<readonly AccountData[]>;
  readonly signAmino: (signerAddress: string, signDoc: StdSignDoc) => Promise<AminoSignResponse>;
}

AminoSignResponse

interface AminoSignResponse {
  readonly signed: StdSignDoc;
  readonly signature: StdSignature;
}

StdSignature

interface StdSignature {
  readonly pub_key: Pubkey;
  readonly signature: string;
}

Pubkey Types

interface Secp256k1Pubkey {
  readonly type: "tendermint/PubKeySecp256k1";
  readonly value: string;
}

interface Ed25519Pubkey {
  readonly type: "tendermint/PubKeyEd25519";
  readonly value: string;
}

interface EthSecp256k1Pubkey {
  readonly type: "os/PubKeyEthSecp256k1";
  readonly value: string;
}

interface MultisigThresholdPubkey {
  readonly type: "tendermint/PubKeyMultisigThreshold";
  readonly value: {
    readonly threshold: string;
    readonly pubkeys: readonly SinglePubkey[];
  };
}

Other Exports

Function/Type	Purpose
`makeCosmoshubPath(account)`	Creates HD path `m/44'/118'/0'/0/{account}`
`omitDefault(value)`	Omit protobuf default values
`isStdTx(value)`	Type guard for StdTx
`makeStdTx(signDoc, signature)`	Create StdTx from sign doc and signature
`extractKdfConfiguration(serialization)`	Extract KDF config from serialized wallet
`executeKdf(password, config)`	Execute key derivation function
`isEthereumSecp256k1Account(account)`	Check if account uses Ethereum secp256k1
`getAminoPubkey(account)`	Get amino pubkey from account data

CosmJS

Concepts

Guides

API Reference

Secp256k1HdWallet

Static Methods

Instance Methods

Instance Properties

Options

Usage

Secp256k1Wallet

Address Functions

Coin Utilities

Pubkey Encoding

Signature Functions

Sign Document Functions

Multisig

Key Types

Coin

StdFee

AminoMsg

StdSignDoc

AccountData

OfflineAminoSigner

AminoSignResponse

StdSignature

Pubkey Types

Other Exports

​Secp256k1HdWallet

​Static Methods

​Instance Methods

​Instance Properties

​Options

​Usage

​Secp256k1Wallet

​Address Functions

​Coin Utilities

​Pubkey Encoding

​Signature Functions

​Sign Document Functions

​Multisig

​Key Types

​Coin

​StdFee

​AminoMsg

​StdSignDoc

​AccountData

​OfflineAminoSigner

​AminoSignResponse

​StdSignature

​Pubkey Types

​Other Exports

Secp256k1HdWallet

Static Methods

Instance Methods

Instance Properties

Options

Usage

Secp256k1Wallet

Address Functions

Coin Utilities

Pubkey Encoding

Signature Functions

Sign Document Functions

Multisig

Key Types

Coin

StdFee

AminoMsg

StdSignDoc

AccountData

OfflineAminoSigner

AminoSignResponse

StdSignature

Pubkey Types

Other Exports