> ## Documentation Index
> Fetch the complete documentation index at: https://docs.walletkit.com/llms.txt
> Use this file to discover all available pages before exploring further.

> Sign a message with wallet's key.

# Sign message

Signing messages can be used for various method of authentication and off-chain operations, which can be put on-chain if necessary.
<Note> Prerequisite: [Create Wallet](/wallets-api/create-wallet/create-scw)</Note>

<Steps>
  <Step title="Obtain user pincode">
    In your app, ask the user for their wallet's 6-digit pincode.

    <Warning>
      You must never store the user pin on your servers.
    </Warning>
  </Step>

  <Step title="Sign Message">
    Fill in the message and sign. Message can be either string or byte array represented in hex string, a common case is to sign a hash.

    <Tabs>
      <Tab title="Signing a string message">
        <CodeGroup>
          ```typescript Typescript theme={null}

          const transaction = await wk.transactions.signMessage({
              network: Network.Base,
              signerWalletAddress: "<walelt address>",
              message: "hello world",
              userPin: "<user pin>",
          });
          ```

          ```bash Curl theme={null}
          curl --request POST \
            --url https://testnet.walletkit.com/transactions/sign-message \
            --header 'X-WalletKit-Project-ID: <Project ID>' \
            --header 'Authorization: Bearer <User Access Token or Your API Key>' \
            --data 
            '{
                  "network": "Base",
                  "signer_wallet_address": "<wallet address>",
                  "message": "hello world",
                  "user_pin": "<user pin>"
            }'
          ```
        </CodeGroup>
      </Tab>

      <Tab title="Signing a bytes array">
        <CodeGroup>
          ```typescript Typescript theme={null}

          const transaction = await wk.transactions.signMessage({
              network: Network.Base,
              signerWalletAddress: "<walelt address>",
              message: "0xa525d9687bb5b71dbe8ce59d98c77a32a5d4ce00dc271b4e3ad0ac72d44e6013",
              message_type: "bytes",
              userPin: "<user pin>",
          });
          ```

          ```bash Curl theme={null}
          curl --request POST \
            --url https://testnet.walletkit.com/transactions/sign-message \
            --header 'X-WalletKit-Project-ID: <Project ID>' \
            --header 'Authorization: Bearer <User Access Token or Your API Key>' \
            --data 
            '{
                  "network": "Base",
                  "signer_wallet_address": "<wallet address>",
                  "message": "0xa525d9687bb5b71dbe8ce59d98c77a32a5d4ce00dc271b4e3ad0ac72d44e6013",
                  "message_type": "bytes",
                  "user_pin": "<user pin>"
            }'
          ```
        </CodeGroup>
      </Tab>
    </Tabs>
  </Step>
</Steps>