Network1 CU

eth_chainId on Avalanche

Returns the chain's EIP-155 chain ID as a hex string. Wallets and libraries call it to confirm they're talking to the expected network.

This is the EIP-155 id used for replay-protected signing — libraries check it on connect, and a mismatch is the usual cause of 'wrong network' errors. It's distinct from net_version (network id); prefer chainId in new code.

Avalanche endpoint (public — no key)

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

Method

eth_chainId

Cost

1 CU

Chain ID

43114

Block time

~2 s

Finality

<2 s (irreversible)

Network on Avalanche

Chain ID 43114 (0xa86a) — the Avalanche C-Chain. The X-Chain and P-Chain are not EVM and don't answer JSON-RPC; subnets each have their own chain ID.

Parameters

None.

cURL

curl https://rpc.nodeflare.app/avax/public \
  -X POST \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","method":"eth_chainId","params":[],"id":1}'

ethers.js

import { ethers } from 'ethers';

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

const result = await provider.send('eth_chainId', []);

Try it live

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

eth_chainId on Avalanche — FAQ

How do I call eth_chainId on Avalanche?

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

What does eth_chainId cost on the free tier?

eth_chainId is weighted at 1 compute unit per call. The free tier includes 2,000,000 CU/month, so that is roughly 2,000,000 eth_chainId calls per month — no credit card.

Is eth_chainId available on the public Avalanche endpoint?

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

Anything Avalanche-specific to know when using eth_chainId?

Chain ID 43114 (0xa86a) — the Avalanche C-Chain. The X-Chain and P-Chain are not EVM and don't answer JSON-RPC; subnets each have their own chain ID.

Call eth_chainId on Avalanche with a free key

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

Get your free API key →