eth_estimateGas

Estimate Gas

POSThttps://site1.moralis-nodes.com/:chain/:apiKey

Estimates the amount of gas required to execute a transaction. This method does not execute the transaction but simulates its execution to estimate the gas amount. It's useful for adjusting gas limits before sending transactions to ensure they succeed without running out of gas.

Note

Please refer to RPC schema page for more details on the RPC params and RPC response definitions of the RPC method.

PATH PARAMS

chainstringrequired

The blockchain to interact with.

ethholeskypolygonamoybscbsc testnetarbitrumarbitrum sepoliaoptimismoptimism testnetbasebase sepolia

apiKeystringrequired

Your API key for authentication.

BODY PARAM

jsonrpcstringrequired

JSON-RPC version (typically 2.0).

idnumberrequired

The request identifier.

methodstringrequired

The JSON-RPC method being invoked.

paramsrpcArrayrequired

Parameters for the transaction to estimate gas for, including details like the sender, receiver, gas price, and value.

[ { "from": "0xa83114A443dA1CecEFC50368531cACE9F37fCCcb", "to": "0x354f3eD35Ae1a182aF933b793e49d3c86CFcDc63", "gasPrice": "0x4a817c800", "value": "0x0", "data": "0xa9059cbb000000000000000000000000407d73d8a49eeb85d32cf465507dd71d507100c10000000000000000000000000000000000000000000000000000000000000064" } ]

Responses

Node.js

// Dependencies to install:
// $ npm install node-fetch --save
// add "type": "module" to package.json

import fetch from 'node-fetch';

const options = {
  method: 'POST',
  headers: {
    accept: 'application/json',
    'content-type': 'application/json'
  },
  body: JSON.stringify({
    "jsonrpc": "2.0",
    "id": 1,
    "method": "eth_estimateGas"
  })
};

fetch('https://site1.moralis-nodes.com/eth/YOUR_API_KEY', options)
  .then(response => response.json())
  .then(response => console.log(response))
  .catch(err => console.error(err));

Python

# Dependencies to install:

# $ python -m pip install requests

import requests

url = "https://site1.moralis-nodes.com/eth/YOUR_API_KEY"

payload = {
  "jsonrpc": "2.0",
  "id": 1,
  "method": "eth_estimateGas"
}
headers = {
  "Accept": "application/json",
  "Content-Type": "application/json"
}

response = requests.request("POST", url, json=payload, headers=headers)

print(response.text)

cURL

curl --request POST \
     --url 'https://site1.moralis-nodes.com/eth/YOUR_API_KEY' \
     --header 'accept: application/json' \
     --header 'content-type: application/json' \
     --data '
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "eth_estimateGas"
}
'

Go

package main

import (
  "fmt"
  "strings"
  "net/http"
  "io/ioutil"
)

func main() {

  url := "https://site1.moralis-nodes.com/eth/YOUR_API_KEY"

  payload := strings.NewReader("{\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"eth_estimateGas\"}")

  req, _ := http.NewRequest("POST", url, payload)

  req.Header.Add("Accept", "application/json")
  req.Header.Add("Content-Type", "application/json")

  res, _ := http.DefaultClient.Do(req)

  defer res.Body.Close()
  body, _ := ioutil.ReadAll(res.Body)

  fmt.Println(res)
  fmt.Println(string(body))

}

PHP

<?php
// Dependencies to install:
// $ composer require guzzlehttp/guzzle

require_once('vendor/autoload.php');

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://site1.moralis-nodes.com/eth/YOUR_API_KEY', [
  'body' => '{"jsonrpc":"2.0","id":1,"method":"eth_estimateGas"}',
  'headers' => [
    'Accept' => 'application/json',
    'Content-Type' => 'application/json',
  ],
]);

echo $response->getBody();

Response Example

200 Returns the estimated gas required for the transaction.

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x5208"
}