estimateGas

Estimates the gas necessary to complete a transaction without submitting it to the network

Import

Import the public actions package so you can call this action.

import "github.com/ChefBingbong/viem-go/actions/public"

Usage

An example showing how to construct a public client and estimate gas for a transaction.

import (
  "context"
  "log"
  "math/big"

  "github.com/ethereum/go-ethereum/common"
  "github.com/ChefBingbong/viem-go/actions/public"
  "github.com/ChefBingbong/viem-go/client"
  "github.com/ChefBingbong/viem-go/client/transport"
  "github.com/ChefBingbong/viem-go/chain/definitions"
)

ctx := context.Background()

publicClient, err := client.CreatePublicClient(client.PublicClientConfig{
  Chain:     definitions.Mainnet,
  Transport: transport.HTTP("https://eth.llamarpc.com"),
})
if err != nil {
  log.Fatal(err)
}
defer func() { _ = publicClient.Close() }()

contractAddr := common.HexToAddress("0x70997970c51812dc3a010c7d01b50e0d17dc79c8")
calldata := common.FromHex("0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2")
senderAddr := common.HexToAddress("0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266")

gas, err := public.EstimateGas(ctx, publicClient, public.EstimateGasParameters{
  Account: &senderAddr,
  To:      &contractAddr,
  Data:    calldata,
})
if err != nil {
  log.Fatal(err)
}
log.Printf("Estimated gas: %d", gas)

Returns

uint64

The estimated gas amount in units of gas.

Parameters

Configuration options accepted by this action.

Account

Type: *common.Address
Optional

The account attached to the transaction (msg.sender).

import (
  "github.com/ethereum/go-ethereum/common"
  "github.com/ChefBingbong/viem-go/actions/public"
)

senderAddr := common.HexToAddress("0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266")
gas, err := public.EstimateGas(ctx, publicClient, public.EstimateGasParameters{
  Account: &senderAddr,
  To:      &contractAddr,
  Data:    calldata,
})

To

Type: *common.Address
Optional

The recipient address. If nil, this is treated as a deployment transaction.

contractAddr := common.HexToAddress("0x70997970c51812dc3a010c7d01b50e0d17dc79c8")
gas, err := public.EstimateGas(ctx, publicClient, public.EstimateGasParameters{
  Account: &senderAddr,
  To:      &contractAddr,
  Data:    calldata,
})

Data

Type: []byte
Optional

The calldata to send.

calldata := common.FromHex("0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2")
gas, err := public.EstimateGas(ctx, publicClient, public.EstimateGasParameters{
  Account: &senderAddr,
  To:      &contractAddr,
  Data:    calldata,
})

Value

Type: *big.Int
Optional

The amount of wei to send.

import "math/big"

gas, err := public.EstimateGas(ctx, publicClient, public.EstimateGasParameters{
  Account: &senderAddr,
  To:      &contractAddr,
  Data:    calldata,
  Value:   big.NewInt(1000000000000000000), // 1 ETH
})

Gas

Type: *uint64
Optional

The gas limit for the transaction.

gasLimit := uint64(21000)
gas, err := public.EstimateGas(ctx, publicClient, public.EstimateGasParameters{
  Account: &senderAddr,
  To:      &contractAddr,
  Data:    calldata,
  Gas:     &gasLimit,
})

MaxFeePerGas

Type: *big.Int
Optional

The max fee per gas (EIP-1559).

import "math/big"

maxFeePerGas := big.NewInt(20000000000) // 20 gwei
gas, err := public.EstimateGas(ctx, publicClient, public.EstimateGasParameters{
  Account:       &senderAddr,
  To:            &contractAddr,
  Data:          calldata,
  MaxFeePerGas:  maxFeePerGas,
})

MaxPriorityFeePerGas

Type: *big.Int
Optional

The max priority fee per gas (EIP-1559).

import "math/big"

maxPriorityFeePerGas := big.NewInt(2000000000) // 2 gwei
gas, err := public.EstimateGas(ctx, publicClient, public.EstimateGasParameters{
  Account:             &senderAddr,
  To:                  &contractAddr,
  Data:                calldata,
  MaxPriorityFeePerGas: maxPriorityFeePerGas,
})

BlockNumber

Type: *uint64
Optional

The block number to estimate at.

blockNum := uint64(12345)
gas, err := public.EstimateGas(ctx, publicClient, public.EstimateGasParameters{
  Account:     &senderAddr,
  To:          &contractAddr,
  Data:        calldata,
  BlockNumber: &blockNum,
})

BlockTag

Type: BlockTag
Optional

The block tag to estimate at (e.g., "latest", "pending").

gas, err := public.EstimateGas(ctx, publicClient, public.EstimateGasParameters{
  Account:  &senderAddr,
  To:       &contractAddr,
  Data:     calldata,
  BlockTag: public.BlockTagSafe,
})

StateOverride

Type: types.StateOverride
Optional

State overrides for the estimation.

JSON-RPC Method

Underlying JSON-RPC method used by this action.

eth_estimateGas