Quickstart

npm install @polymarket/clob-client ethers@5

import { ClobClient } from "@polymarket/clob-client";
import { Wallet } from "ethers"; // v5.8.0

const HOST = "https://clob.polymarket.com";
const CHAIN_ID = 137; // Polygon mainnet
const signer = new Wallet(process.env.PRIVATE_KEY);

// Derive API credentials
const tempClient = new ClobClient(HOST, CHAIN_ID, signer);
const apiCreds = await tempClient.createOrDeriveApiKey();

// Initialize trading client
const client = new ClobClient(
  HOST,
  CHAIN_ID,
  signer,
  apiCreds,
  0, // EOA
  signer.address,
);

import { Side, OrderType } from "@polymarket/clob-client";

const response = await client.createAndPostOrder(
  {
    tokenID: "YOUR_TOKEN_ID",
    price: 0.5,
    size: 10,
    side: Side.BUY,
  },
  {
    tickSize: "0.01",
    negRisk: false, // Set to true for multi-outcome markets
  },
  OrderType.GTC,
);

console.log("Order ID:", response.orderID);
console.log("Status:", response.status);

// View all open orders
const openOrders = await client.getOpenOrders();
console.log(`You have ${openOrders.length} open orders`);

// View your trade history
const trades = await client.getTrades();
console.log(`You've made ${trades.length} trades`);

// Cancel an order
await client.cancelOrder(response.orderID);