TypeScript SDK: Account (Signer)

Purpose

Guide creation and use of Account (signer) in @aptos-labs/ts-sdk. An Account holds address + key material and can sign transactions and messages. Creating an Account does NOT create the account on-chain; use faucet or transfer to fund it.

ALWAYS

Use Account.generate() or Account.fromPrivateKey() only in server/script – never in frontend; use wallet adapter for end users.
Load private keys from env (e.g. process.env.PRIVATE_KEY) on server – never hardcode.
Use account.accountAddress when building transactions – pass as sender/secondary signers.
Use aptos.signAndSubmitTransaction({ signer: account, transaction }) with the same Account instance that holds the key.

NEVER

Do not use Account.generate() or raw private keys in browser/frontend – use wallet adapter.
Do not hardcode private keys in source or commit to git.
Do not confuse Account (API namespace) with Account (signer class) – API is aptos.account.*; signer is the class from Account module (e.g. Account.fromPrivateKey).

Account types (signing schemes)

Type	Class	Use case
Ed25519 (legacy)	`Ed25519Account`	Single Ed25519 key, legacy auth
SingleKey	`SingleKeyAccount`	Ed25519 or Secp256k1, unified auth
MultiKey	`MultiKeyAccount`	Multi-sig
Keyless	`KeylessAccount`	Keyless (e.g. OIDC)
Federated Keyless	`FederatedKeylessAccount`	Federated keyless

Generate new account (server/script only)

import { Account, SigningSchemeInput } from "@aptos-labs/ts-sdk";

// Default: Ed25519 legacy
const ed25519Account = Account.generate();

// SingleKey (unified) with Ed25519
const singleKeyAccount = Account.generate({ scheme: SigningSchemeInput.Ed25519, legacy: false });

// SingleKey with Secp256k1
const secpAccount = Account.generate({ scheme: SigningSchemeInput.Secp256k1 });

// Access address and public key
const address = ed25519Account.accountAddress;
const pubKey = ed25519Account.publicKey;

From private key

import { Account, Ed25519PrivateKey, Secp256k1PrivateKey } from "@aptos-labs/ts-sdk";

// Ed25519 legacy (default)
const privateKeyHex = process.env.PRIVATE_KEY!; // e.g. "0x..." or AIP-80 prefixed
const privateKey = new Ed25519PrivateKey(privateKeyHex);
const account = Account.fromPrivateKey({ privateKey });

// Ed25519 SingleKey (unified)
const accountSingle = Account.fromPrivateKey({
  privateKey: new Ed25519PrivateKey(privateKeyHex),
  legacy: false,
});

// Secp256k1 (always SingleKey)
const secpKey = new Secp256k1PrivateKey(process.env.SECP_KEY!);
const accountSecp = Account.fromPrivateKey({ privateKey: secpKey });

// Optional: fixed address (e.g. after key rotation)
const accountWithAddr = Account.fromPrivateKey({
  privateKey,
  address: "0x...",
});

From mnemonic (derivation path)

import { Account } from "@aptos-labs/ts-sdk";

const mnemonic = "word1 word2 ... word12";
const path = "m/44'/637'/0'/0'/0'"; // Aptos BIP-44 path

// Ed25519 legacy
const acc = Account.fromDerivationPath({ mnemonic, path });

// Ed25519 SingleKey
const accSingle = Account.fromDerivationPath({ mnemonic, path, legacy: false });

// Secp256k1
const accSecp = Account.fromDerivationPath({
  scheme: SigningSchemeInput.Secp256k1,
  mnemonic,
  path,
});

Auth key (for rotation / lookup)

const authKey = Account.authKey({ publicKey: account.publicKey });
// Use authKey.derivedAddress() for address derivation; useful for multi-account lookup

Serialization (toHex / fromHex)

Use when persisting or sending account (e.g. server-only, never expose private key to frontend):

import { Account, AccountUtils } from "@aptos-labs/ts-sdk";

const account = Account.generate();

// Serialize to hex (includes private key – treat as secret)
const hex = AccountUtils.toHexString(account);

// Deserialize back
const restored = AccountUtils.fromHex(hex);

// Typed deserialize
const edAccount = AccountUtils.ed25519AccountFromHex(hex);
const singleAccount = AccountUtils.singleKeyAccountFromHex(hex);
const multiAccount = AccountUtils.multiKeyAccountFromHex(hex);
const keylessAccount = AccountUtils.keylessAccountFromHex(hex);

Signing

// Sign message (returns Signature)
const sig = account.sign(messageHex);

// Sign transaction (returns Signature; for submit use aptos.transaction.sign + submit)
const txSig = account.signTransaction(rawTransaction);

// With authenticator (used by SDK internally for submit)
const auth = account.signWithAuthenticator(messageHex);

Verify signature

const ok = account.verifySignature({ message: messageHex, signature: sig });

// Async (if key type needs on-chain state)
const okAsync = await account.verifySignatureAsync({
  aptosConfig: aptos.config,
  message: messageHex,
  signature: sig,
});

Derive account from private key (on-chain lookup)

When the same key may have multiple on-chain accounts (e.g. after rotation), use internal derivation + lookup:

// Returns list of accounts owned by this key on chain
const accounts = await aptos.deriveOwnedAccountsFromSigner({
  signer: account,
});
// Prefer wallet or explicit address for production; this is for scripts/tooling

Common mistakes

Mistake	Correct approach
Using `Account.generate()` in frontend	Use wallet adapter; generate only in server/script
Hardcoding private key	Load from `process.env` (server) and never commit
Using `aptos.account` as signer	`aptos.account` is API namespace; signer is `Account.fromPrivateKey()` / `Account.generate()`
Expecting account to exist on-chain after generate	Fund with faucet or transfer first

References

SDK: src/account/Account.ts, src/account/Ed25519Account.ts, src/account/AccountUtils.ts, src/api/account.ts
Pattern: TYPESCRIPT_SDK.md
Related: ts-sdk-client, ts-sdk-transactions, use-ts-sdk

ts-sdk-account