What is the Metis RPC and how do you connect to the Metis Andromeda network?

Quick recommendation: choose an RPC provider based on your workload

If you are building a production dApp on Metis, the public RPC endpoint https://andromeda.metis.io/?owner=1088 is fine for prototyping, but it is not designed for high traffic or guaranteed availability. For anything beyond a hackathon or a small test, you should evaluate a managed RPC provider that offers dedicated throughput, WebSocket support, and archive data. Start by checking the supported RPC networks page to see which providers cover Metis, then compare their pricing against your expected request volume. A dedicated node gives you a private endpoint with higher rate limits and more consistent latency, which matters for indexers, trading bots, and analytics platforms.

What is Metis Andromeda?

Metis Andromeda is an Ethereum Layer 2 optimistic rollup that launched in 2021. It was originally forked from Optimism but has evolved into its own network with a focus on Decentralized Autonomous Companies (DACs). The network uses METIS as its native gas token, so transaction fees are paid in METIS rather than ETH. Metis is EVM-compatible, meaning you can deploy Solidity smart contracts and use familiar tools like Hardhat, Foundry, and ethers.js without major changes.

The network is known for fast block times (around 1-2 seconds) and low transaction costs, making it attractive for DeFi, gaming, and other high-frequency applications. To interact with Metis, you need an RPC endpoint that speaks the Ethereum JSON-RPC protocol. The official endpoint is https://andromeda.metis.io/?owner=1088, but many third-party providers offer alternative endpoints with different performance characteristics.

Chain settings at a glance

Before you connect to Metis, you need the correct network parameters. Here is the essential information for the Metis Andromeda mainnet:

These values are also listed on ChainList and other network directories. Always double-check the chain ID before sending transactions—using the wrong chain ID can result in lost funds.

How to add Metis to MetaMask or another wallet

Adding Metis to a wallet is straightforward. In MetaMask, open the network selection dropdown, click "Add network," and fill in the details from the table above. Alternatively, you can use a one-click add button from a site like ChainList or revoke.cash. Here is a typical configuration for a wallet:

{
  "networkName": "Metis Andromeda Mainnet",
  "rpcUrl": "https://andromeda.metis.io/?owner=1088",
  "chainId": 1088,
  "currencySymbol": "METIS",
  "blockExplorerUrl": "https://andromeda-explorer.metis.io"
}

For programmatic access, you can use ethers.js or viem to connect to the network. Here is an example using ethers.js:

import { ethers } from "ethers";

const provider = new ethers.JsonRpcProvider("https://andromeda.metis.io/?owner=1088");
const network = await provider.getNetwork();
console.log("Chain ID:", network.chainId); // 1088

const blockNumber = await provider.getBlockNumber();
console.log("Latest block:", blockNumber);

Public vs. private RPC endpoints: what to consider

Public RPC endpoints are convenient because they require no sign-up and work out of the box. However, they are often rate-limited, can become congested during peak usage, and may not offer WebSocket or archive data. For production applications, you need a more reliable solution.

Private RPC endpoints, such as those provided by OnFinality, give you a dedicated URL that is not shared with other users. This means higher rate limits, more consistent latency, and access to advanced features like trace methods or archive data. When evaluating a provider, consider the following:

• Throughput: How many requests per second can you sustain? Public endpoints may cap you at a few requests per second, while private endpoints can handle hundreds or more.
• WebSocket support: If your dApp needs real-time updates (e.g., for price feeds or transaction status), you need a WSS endpoint.
• Archive data: Some applications require historical state. Not all providers offer archive nodes, so check before committing.
• Geographic distribution: A provider with multiple regions can reduce latency for users around the world.

OnFinality offers both shared and dedicated node options for Metis. You can start with a free public endpoint and upgrade to a dedicated node as your project grows. See our RPC pricing for details.

Making JSON-RPC calls to Metis

Once you have an endpoint, you can interact with Metis using standard Ethereum JSON-RPC methods. Here is a simple curl example to get the latest block number:

curl -X POST https://andromeda.metis.io/?owner=1088 \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}'

The response will look like:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x15f2e0c"
}

You can also use WebSocket for real-time subscriptions. For example, to subscribe to new block headers:

const ws = new WebSocket("wss://metis-rpc.publicnode.com");
ws.onopen = () => {
  ws.send(JSON.stringify({
    jsonrpc: "2.0",
    method: "eth_subscribe",
    params: ["newHeads"],
    id: 1
  }));
};
ws.onmessage = (event) => {
  console.log(event.data);
};

Common pitfalls and troubleshooting

Even with the right endpoint, you may run into issues. Here are a few common problems and how to resolve them:

• Incorrect chain ID: If you set the wrong chain ID, transactions will be rejected. Always use 1088 for Metis Andromeda.
• Rate limiting: Public endpoints often return 429 Too Many Requests. If you see this, consider upgrading to a private endpoint or implementing retry logic with exponential backoff.
• WebSocket disconnects: Some providers close idle WebSocket connections. Implement a heartbeat mechanism to keep the connection alive.
• Missing archive data: If you need historical state, ensure your provider offers archive nodes. Not all do.

For more advanced troubleshooting, check the RPC troubleshooting guide for general best practices.

How to choose a Metis RPC provider for production

When your dApp is ready for mainnet, you need a provider that can scale with you. Here is a checklist to guide your decision:

• Reliability: Look for providers with a track record of high uptime. Avoid making absolute claims, but check their status pages and SLAs.
• Performance: Test latency from multiple regions. A provider with global points of presence will offer better performance for a distributed user base.
• Features: Does the provider support WebSocket, archive data, and trace methods? These are often essential for complex dApps.
• Pricing: Compare costs based on your expected request volume. Some providers charge per request, others offer flat monthly plans.
• Support: In production, you need responsive support. Check if the provider offers 24/7 support and a dedicated channel.

OnFinality provides a dedicated node service that gives you a private, high-performance endpoint for Metis. You can also use our public RPC endpoint for testing. For a full list of supported networks, see the networks page.

Key Takeaways

• Metis Andromeda is an EVM-compatible Layer 2 with chain ID 1088 and METIS as the gas token.
• The official RPC endpoint is https://andromeda.metis.io/?owner=1088, but public endpoints may be rate-limited.
• For production, evaluate private RPC providers based on throughput, WebSocket support, archive data, and geographic coverage.
• Use standard Ethereum JSON-RPC methods to interact with Metis; tools like ethers.js and viem work out of the box.
• Always verify chain settings before sending transactions to avoid errors.

Frequently Asked Questions

What is the Metis RPC URL? The official RPC URL is https://andromeda.metis.io/?owner=1088. You can also use third-party endpoints like https://metis.api.onfinality.io/public.

What is the Metis chain ID? The chain ID for Metis Andromeda mainnet is 1088.

Is Metis an Ethereum Layer 2? Yes, Metis is an optimistic rollup built on Ethereum, using METIS as its native gas token.

How do I get METIS tokens for gas? You can bridge ETH or other assets to Metis using the official bridge, or purchase METIS on exchanges and transfer it to your wallet.

Can I use WebSocket with Metis? Yes, many providers offer WebSocket endpoints for real-time updates. Check with your provider for the WSS URL.

Does OnFinality support Metis? Yes, OnFinality offers public and dedicated RPC endpoints for Metis. See our supported networks page for more details.