signTypedData
Signs typed data and calculates an Ethereum-specific signature in EIP-191 format: keccak256("\x19Ethereum Signed Message:\n" + len(message) + message)).
Usage
ts
import { account, walletClient } from './config'
import { domain, types } from './data'
const signature = await walletClient.signTypedData({
account,
domain,
types,
primaryType: 'Mail',
message: {
from: {
name: 'Cow',
wallet: '0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826',
},
to: {
name: 'Bob',
wallet: '0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB',
},
contents: 'Hello, Bob!',
},
})
ts
// All properties on a domain are optional
export const domain = {
name: 'Ether Mail',
version: '1',
chainId: 1,
verifyingContract: '0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC',
} as const
// The named list of all type definitions
export const types = {
Person: [
{ name: 'name', type: 'string' },
{ name: 'wallet', type: 'address' },
],
Mail: [
{ name: 'from', type: 'Person' },
{ name: 'to', type: 'Person' },
{ name: 'contents', type: 'string' },
],
} as const
ts
import { createWalletClient, custom } from 'viem'
import { privateKeyToAccount } from 'viem/accounts'
import { mainnet } from 'viem/chains'
export const walletClient = createWalletClient({
chain: mainnet,
transport: custom(window.ethereum)
})
// JSON-RPC Account
export const [account] = await walletClient.getAddresses()
// Local Account
export const account = privateKeyToAccount('0x...')
Account Hoisting
If you do not wish to pass an account to every signTypedData, you can also hoist the Account on the Wallet Client (see config.ts).
ts
import { walletClient } from './config'
import { domain, types } from './data'
const signature = await walletClient.signTypedData({
domain,
types,
primaryType: 'Mail',
message: {
from: {
name: 'Cow',
wallet: '0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826',
},
to: {
name: 'Bob',
wallet: '0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB',
},
contents: 'Hello, Bob!',
},
})
ts
// All properties on a domain are optional
export const domain = {
name: 'Ether Mail',
version: '1',
chainId: 1,
verifyingContract: '0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC',
} as const
// The named list of all type definitions
export const types = {
Person: [
{ name: 'name', type: 'string' },
{ name: 'wallet', type: 'address' },
],
Mail: [
{ name: 'from', type: 'Person' },
{ name: 'to', type: 'Person' },
{ name: 'contents', type: 'string' },
],
} as const
ts
import { createWalletClient, custom } from 'viem'
// Retrieve Account from an EIP-1193 Provider.
const [account] = await window.ethereum.request({
method: 'eth_requestAccounts'
})
export const walletClient = createWalletClient({
account,
transport: custom(window.ethereum)
})
ts
import { createWalletClient, custom } from 'viem'
import { privateKeyToAccount } from 'viem/accounts'
export const walletClient = createWalletClient({
account: privateKeyToAccount('0x...'),
transport: custom(window.ethereum)
})
Returns
0x${string}
The signed data.
Parameters
account
- Type:
Account | Address
The Account to use for signing.
Accepts a JSON-RPC Account or Local Account (Private Key, etc).
ts
const signature = await walletClient.signTypedData({
account: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
domain: {
name: 'Ether Mail',
version: '1',
chainId: 1,
verifyingContract: '0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC',
},
types,
primaryType: 'Mail',
message: {
from: {
name: 'Cow',
wallet: '0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826',
},
to: {
name: 'Bob',
wallet: '0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB',
},
contents: 'Hello, Bob!',
},
})
domain
Type: TypedDataDomain
The typed data domain.
ts
const signature = await walletClient.signTypedData({
account: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
domain: {
name: 'Ether Mail',
version: '1',
chainId: 1,
verifyingContract: '0xCcCCccccCCCCcCCCCCCcCcCccCcCCCcCcccccccC',
},
types,
primaryType: 'Mail',
message: {
from: {
name: 'Cow',
wallet: '0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826',
},
to: {
name: 'Bob',
wallet: '0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB',
},
contents: 'Hello, Bob!',
},
})
types
The type definitions for the typed data.
ts
const signature = await walletClient.signTypedData({
account: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
domain,
types: {
Person: [
{ name: 'name', type: 'string' },
{ name: 'wallet', type: 'address' },
],
Mail: [
{ name: 'from', type: 'Person' },
{ name: 'to', type: 'Person' },
{ name: 'contents', type: 'string' },
],
},
primaryType: 'Mail',
message: {
from: {
name: 'Cow',
wallet: '0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826',
},
to: {
name: 'Bob',
wallet: '0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB',
},
contents: 'Hello, Bob!',
},
})
primaryType
Type: Inferred string.
The primary type to extract from types and use in value.
ts
const signature = await walletClient.signTypedData({
account: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
domain,
types: {
Person: [
{ name: 'name', type: 'string' },
{ name: 'wallet', type: 'address' },
],
Mail: [
{ name: 'from', type: 'Person' },
{ name: 'to', type: 'Person' },
{ name: 'contents', type: 'string' },
],
},
primaryType: 'Mail',
message: {
from: {
name: 'Cow',
wallet: '0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826',
},
to: {
name: 'Bob',
wallet: '0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB',
},
contents: 'Hello, Bob!',
},
})
message
Type: Inferred from types & primaryType.
ts
const signature = await walletClient.signTypedData({
account: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
domain,
types: {
Person: [
{ name: 'name', type: 'string' },
{ name: 'wallet', type: 'address' },
],
Mail: [
{ name: 'from', type: 'Person' },
{ name: 'to', type: 'Person' },
{ name: 'contents', type: 'string' },
],
},
primaryType: 'Mail',
message: {
from: {
name: 'Cow',
wallet: '0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826',
},
to: {
name: 'Bob',
wallet: '0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB',
},
contents: 'Hello, Bob!',
},
})
Live Example
Check out the usage of signTypedData in the live Sign Typed Data Example below.
JSON-RPC Methods
- JSON-RPC Accounts:
- Local Accounts
- Signs locally. No JSON-RPC request.