estimateContractGas
Estimates the gas required to successfully execute a contract write function call.
Usage
Below is a very basic example of how to estimate gas (with no arguments).
The mint function accepts no arguments, and returns a token ID.
ts
import { publicClient } from './client'
import { wagmiAbi } from './abi'
const gas = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint',
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
})
// 69420n
ts
export const wagmiAbi = [
  ...
  {
    inputs: [],
    name: "mint",
    outputs: [{ name: "", type: "uint32" }],
    stateMutability: "view",
    type: "function",
  },
  ...
] as const;
ts
import { createPublicClient, http } from 'viem'
import { mainnet } from 'viem/chains'
export const publicClient = createPublicClient({
  chain: mainnet,
  transport: http()
})
Passing Arguments
If your function requires argument(s), you can pass them through with the args attribute.
TypeScript types for args will be inferred from the function name & ABI, to guard you from inserting the wrong values.
For example, the mint function name below requires a tokenId argument, and it is typed as [number].
ts
import { publicClient } from './client'
import { wagmiAbi } from './abi'
const gas = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint',
  args: [69420],
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
})
// 69420n
ts
export const wagmiAbi = [
  ...
  {
    inputs: [{ name: "owner", type: "uint32" }],
    name: "mint",
    outputs: [{ name: "", type: "uint32" }],
    stateMutability: "view",
    type: "function",
  },
  ...
] as const;
ts
import { createPublicClient, http } from 'viem'
import { mainnet } from 'viem/chains'
export const publicClient = createPublicClient({
  chain: mainnet,
  transport: http()
})
Return Value
bigint
The gas estimate.
Parameters
address
- Type: 
Address 
The contract address.
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2', 
  abi: wagmiAbi,
  functionName: 'mint',
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
})
abi
- Type: 
Abi 
The contract's ABI.
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi, 
  functionName: 'mint',
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
})
functionName
- Type: 
string 
A function to extract from the ABI.
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint', 
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
})
from
- Type: 
Address 
The sender of the call.
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint',
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266' 
})
accessList (optional)
- Type: 
AccessList 
The access list.
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint',
  args: [69420],
  accessList: [{ 
    address: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
    storageKeys: ['0x1'],
  }], 
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
})
args (optional)
- Type: Inferred from ABI.
 
Arguments to pass to function call.
ts
const { result } = await publicClient.estimateContractGas({
  address: '0x1dfe7ca09e99d10835bf73044a23b73fc20623df',
  abi: wagmiAbi,
  functionName: 'balanceOf',
  args: ['0xa5cc3c03994DB5b0d9A5eEdD10CabaB0813678AC'], 
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
})
gasPrice (optional)
- Type: 
bigint 
The price (in wei) to pay per gas. Only applies to Legacy Transactions.
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint',
  args: [69420],
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
  gasPrice: parseGwei('20'), 
})
maxFeePerGas (optional)
- Type: 
bigint 
Total fee per gas (in wei), inclusive of maxPriorityFeePerGas. Only applies to EIP-1559 Transactions
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint',
  args: [69420],
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
  maxFeePerGas: parseGwei('20'),  
})
maxPriorityFeePerGas (optional)
- Type: 
bigint 
Max priority fee per gas (in wei). Only applies to EIP-1559 Transactions
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint',
  args: [69420],
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
  maxFeePerGas: parseGwei('20'),
  maxPriorityFeePerGas: parseGwei('2'), 
})
nonce (optional)
- Type: 
number 
Unique number identifying this transaction.
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint',
  args: [69420],
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
  nonce: 69 
})
value (optional)
- Type: 
number 
Value in wei sent with this transaction.
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint',
  args: [69420],
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
  value: parseEther('1') 
})
blockNumber (optional)
- Type: 
number 
The block number to perform the read against.
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint',
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
  blockNumber: 15121123n, 
})
blockTag (optional)
- Type: 
'latest' | 'earliest' | 'pending' | 'safe' | 'finalized' - Default: 
'latest' 
The block tag to perform the read against.
ts
const { result } = await publicClient.estimateContractGas({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: wagmiAbi,
  functionName: 'mint',
  from: '0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266',
  blockTag: 'safe', 
})