> For the complete documentation index, see [llms.txt](/llms.txt)

# Sign Personal Message

Sign an arbitrary message with the connected wallet for authentication or proof of ownership.



The `signPersonalMessage` action prompts the connected wallet to sign a personal message. This is
useful for authentication, proof of ownership, or other scenarios where you need cryptographic proof
that a user controls a specific account.

## Usage [#usage]

```typescript
import { createDAppKit } from '@mysten/dapp-kit-core';

const dAppKit = createDAppKit({/* config */});

const message = new TextEncoder().encode('Please sign this message');
const result = await dAppKit.signPersonalMessage({
	message,
});

console.log('Message bytes:', result.bytes);
console.log('Signature:', result.signature);
```

## Parameters [#parameters]

* **`message`:** `Uint8Array` - The message to sign as a byte array
* **`account`** (optional) - `UiWalletAccount` - The account to sign with. Defaults to the currently
  connected account. Must belong to the connected wallet, otherwise a `WalletAccountNotFoundError`
  is thrown. Lets you sign with a specific account without changing the selected account via
  `switchAccount`.
* **`network`** (optional) - The network to sign against (a configured network identifier such as
  `'mainnet'`). Defaults to the active network. The signing chain is derived from it, so you can
  sign against a network without changing the active network via `switchNetwork`. Throws a
  `ChainNotSupportedError` if the signing account does not support the network. This matters for
  network-bound signatures such as zkLogin.

## Return value [#return-value]

Returns a `Promise` that resolves to an object containing:

* **`bytes`:** `string` - Base64 encoded message bytes
* **`signature`:** `string` - Base64 encoded signature

## Message format [#message-format]

The message parameter must be a `Uint8Array`. Common patterns for creating byte arrays:

```typescript
const textMessage = new TextEncoder().encode('Hello, Sui!');
await dAppKit.signPersonalMessage({ message: textMessage });

const jsonMessage = new TextEncoder().encode(
	JSON.stringify({ action: 'sign', timestamp: Date.now() }),
);
await dAppKit.signPersonalMessage({ message: jsonMessage });
```

## Security considerations [#security-considerations]

### Message content [#message-content]

* Always display the message content clearly to users before signing
* Avoid signing opaque or encoded data that users cannot understand
* Include human-readable prefixes for different message types
* Consider adding timestamps to prevent replay attacks