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.

ethsepoliaholeskybasebase-sepoliapolygonamoybscbsc-testnetarbitrumarbitrum-sepoliaoptimismoptimism-sepoliagnosisgnosis-testnetlinealinea-sepoliaavalanchemoonbeammoonrivermoonbaseblastblast-sepoliamantlemantle-sepoliapolygon-zkevmpolygon-zkevm-cardonazksynczksync-sepoliazetachainzetachain-testnetfantomopbnbflowflow-testnetroninronin-testnetlisklisk-sepoliapulse

apiKeystringrequired

Your API key for authentication.

BODY PARAM

Request Bodyobjectrequired

The request payload for estimating gas required for a transaction.

{ "jsonrpc": "2.0", "id": 1, "method": "eth_estimateGas" }

Responses

200Returns the estimated gas required for the transaction.

400Bad Request

404Not Found

429Too Many Requests

500Internal Server Error

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"
}
'

Node.js

// Node.js v18+ has native fetch support
// No additional dependencies required

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)

Go

package main

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

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, _ := io.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"
}