Contract calls5 CU

eth_estimateGas on Base

Simulates a transaction and returns the gas it would consume, without broadcasting it. Wallets call this before signing to set a sensible gas limit.

It simulates once at current state, so a tx whose cost depends on other pending txs can be under-estimated — pad the result (e.g. +20%). On L2s the figure covers L2 execution only; the L1 data fee is added at inclusion.

Base endpoint (public — no key)

https://rpc.nodeflare.app/base/public

Method

eth_estimateGas

Cost

5 CU

Chain ID

8453

Block time

~2 s

Finality

~2 s soft · L1-final ~13 min

Contract calls on Base

eth_estimateGas on Base covers L2 execution only — the L1 data fee is added on top at inclusion time. Budget from the receipt's l1Fee on similar transactions, not from the gas estimate alone.

Parameters

[callObject]

cURL

curl https://rpc.nodeflare.app/base/public \
  -X POST \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","method":"eth_estimateGas","params":[{"to": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913", "data": "0x18160ddd"}],"id":1}'

The example targets the USDC contract on Base — you can run it as-is.

ethers.js

import { ethers } from 'ethers';

const provider = new ethers.JsonRpcProvider(
  'https://rpc.nodeflare.app/base/public'
);

const result = await provider.send('eth_estimateGas', [{"to": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913", "data": "0x18160ddd"}]);

Try it live

Runs the example above against the public Base endpoint — straight from your browser.

eth_estimateGas on Base — FAQ

How do I call eth_estimateGas on Base?

POST a JSON-RPC 2.0 request with "method": "eth_estimateGas" to NodeFlare's Base endpoint at https://rpc.nodeflare.app/base/public. No API key is required for the public endpoint.

What does eth_estimateGas cost on the free tier?

eth_estimateGas is weighted at 5 compute units per call. The free tier includes 2,000,000 CU/month, so that is roughly 400,000 eth_estimateGas calls per month — no credit card.

Is eth_estimateGas available on the public Base endpoint?

Yes. eth_estimateGas works on the public Base endpoint (https://rpc.nodeflare.app/base/public) with no API key, rate-limited per IP. A free key adds higher limits and a dedicated path.

Anything Base-specific to know when using eth_estimateGas?

eth_estimateGas on Base covers L2 execution only — the L1 data fee is added on top at inclusion time. Budget from the receipt's l1Fee on similar transactions, not from the gas estimate alone.

Call eth_estimateGas on Base with a free key

2,000,000 compute units/month, heavy methods unlocked, every chain included. No credit card.

Get your free API key →