Monad API Quickstart

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Monad is a high-performance Ethereum-compatible L1. Monad materially advances the efficient frontier in the balance between decentralization and scalability.

Please note that we currently only support the Monad testnet

The Monad API allows interaction with the Monad network through a set of JSON-RPC methods. Its design is familiar to developers who have worked with Ethereum's JSON-RPC APIs, making it intuitive and straightforward to use.

Let's use the viem package to create a Monad client connected to Alchemy and fetch the latest block number!

npm install --save viem

import { createPublicClient, http, defineChain } from "viem";
 
const monadTestnet = defineChain({
  id: 10143,
  name: "Monad Testnet",
  nativeCurrency: { name: "MON", symbol: "MON", decimals: 18 },
  rpcUrls: {
    default: { http: ["https://monad-testnet.g.alchemy.com/v2/YOUR_ALCHEMY_API_KEY"] },
  },
});
 
const client = createPublicClient({
  chain: monadTestnet,
  transport: http("https://monad-testnet.g.alchemy.com/v2/YOUR_ALCHEMY_API_KEY"),
});

Now that you've created a client connected to Alchemy, you can continue with some basics:

const blockNumber = await client.getBlockNumber();
console.log("Current block number:", blockNumber);

const balance = await client.getBalance({ address: "0xab5801a7d398351b8be11c439e05c5b3259aec9b" });
console.log("Balance (MON):", Number(balance) / 1e18);

const block = await client.getBlock({
  blockNumber: blockNumber, // from previous example
});
console.log(block);

const tx = await client.getTransaction({ hash: "0xYOUR_TX_HASH" });
console.log(tx);

const receipt = await client.getTransactionReceipt({
  hash: "0xYOUR_TX_HASH"
});
console.log(receipt);

For the full list of Monad APIs, see the Monad API Endpoints.