RPC method

eth_chainId on Manta Pacific

Supported on SwiftNodes

Everything below was measured on 2026-10-13 by calling eth_chainId on Manta Pacific through the same endpoint customers use, and is re-measured weekly.

What eth_chainId does

Returns the chain ID (EIP-155) as a hex string. Wallets and libraries check it before signing, and the signature commits to it, so a transaction signed for one chain cannot be replayed on another.

Manta Pacific chain ID, as measured

net_version returns the same number as decimal text. Older tools read net_version; use eth_chainId, which is the value signatures commit to.

We sent Manta Pacific a legacy transaction signed without a chain ID (pre-EIP-155). Its nodes did not reject it for that: the answer was about the empty balance ("insufficient funds for gas * price + value: have 0 want 42013797001"). Unprotected transactions are accepted at the RPC, so replay protection depends on your wallet signing with the chain ID.

eth_chainId0xa9 (169)
net_version169

Example request

curl -s https://rpc.swiftnodes.io/rpc/manta?key=YOUR_API_KEY \
  -X POST -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"eth_chainId","params":[]}'
// Check you are on Manta Pacific before signing
import { createPublicClient, http } from "viem";

const client = createPublicClient({
  transport: http("https://rpc.swiftnodes.io/rpc/manta?key=YOUR_API_KEY"),
});

const id = await client.getChainId(); // 169
if (id !== 169) throw new Error(`wrong chain: ${id}`);

// Add Manta Pacific to a browser wallet
await window.ethereum.request({
  method: "wallet_addEthereumChain",
  params: [{
    chainId: "0xa9",
    chainName: "Manta Pacific",
    nativeCurrency: { name: "ETH", symbol: "ETH", decimals: 18 },
    rpcUrls: ["https://rpc.swiftnodes.io/rpc/manta?key=YOUR_API_KEY"],
  }],
});

Other methods on Manta Pacific

eth_chainId on other chains

Frequently asked questions

Does Manta Pacific support eth_chainId?

Yes. eth_chainId answered on the SwiftNodes Manta Pacific endpoint when our weekly probe called it through the customer path (2026-10-13).

What is the Manta Pacific chain ID?

169 in decimal, 0xa9 in hex, as returned by eth_chainId on 2026-10-13.

How do I add Manta Pacific to MetaMask?

Call wallet_addEthereumChain with chainId 0xa9, the native currency ETH with 18 decimals, and your RPC URL; the example on this page has the full object.

Manta Pacific endpoints, live block height and WebSocket status are on the Manta Pacific RPC page.

One key covers every chain we serve, and SwiftNodes has a free tier.