RPC method

eth_chainId on Plasma

Supported on SwiftNodes

Everything below was measured on 2026-10-13 by calling eth_chainId on Plasma 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.

Plasma 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 Plasma 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 378133581001"). Unprotected transactions are accepted at the RPC, so replay protection depends on your wallet signing with the chain ID.

eth_chainId0x2611 (9,745)
net_version9745

Example request

curl -s https://rpc.swiftnodes.io/rpc/plasma?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 Plasma before signing
import { createPublicClient, http } from "viem";

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

const id = await client.getChainId(); // 9745
if (id !== 9745) throw new Error(`wrong chain: ${id}`);

// Add Plasma to a browser wallet
await window.ethereum.request({
  method: "wallet_addEthereumChain",
  params: [{
    chainId: "0x2611",
    chainName: "Plasma",
    nativeCurrency: { name: "XPL", symbol: "XPL", decimals: 18 },
    rpcUrls: ["https://rpc.swiftnodes.io/rpc/plasma?key=YOUR_API_KEY"],
  }],
});

Other methods on Plasma

eth_chainId on other chains

Frequently asked questions

Does Plasma support eth_chainId?

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

What is the Plasma chain ID?

9745 in decimal, 0x2611 in hex, as returned by eth_chainId on 2026-10-13.

How do I add Plasma to MetaMask?

Call wallet_addEthereumChain with chainId 0x2611, the native currency XPL with 18 decimals, and your RPC URL; the example on this page has the full object.

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

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