signMessage (Local Account) 
Calculates an Ethereum-specific signature in EIP-191 format: keccak256("\x19Ethereum Signed Message:\n" + len(message) + message)).
With the calculated signature, you can:
- use 
verifyMessageto verify the signature, - use 
recoverMessageAddressto recover the signing address from a signature. 
Usage 
ts
import { privateKeyToAccount } from 'viem/accounts'
const account = privateKeyToAccount('0x...')
const signature = await account.signMessage({
  // Hex data representation of message.
  message: { raw: '0x68656c6c6f20776f726c64' },
})
// "0xa461f509887bd19e312c0c58467ce8ff8e300d3c1a90b608a760c5b80318eaf15fe57c96f9175d6cd4daad4663763baa7e78836e067d0163e9a2ccf2ff753f5b1b"Returns 
The signed message.
Parameters 
message 
- Type: 
string | { raw: Hex | ByteArray } 
Message to sign.
By default, viem signs the UTF-8 representation of the message.
ts
const signature = await account.signMessage({
  message: 'hello world', 
})To sign the data representation of the message, you can use the raw attribute.
ts
const signature = await account.signMessage({
  message: { raw: '0x68656c6c6f20776f726c64' }, 
})