Polymarket Python CLOB Client

Python client for the Polymarket Central Limit Order Book (CLOB).

Documentation

Installation

# install from PyPI (Python 3.9>)
pip install py-clob-client

Usage

The examples below are short and copy‑pasteable.

• What you need:
  • Python 3.9+
  • Private key that owns funds on Polymarket
  • Optional: a proxy/funder address if you use an email or smart‑contract wallet
  • Tip: store secrets in environment variables (e.g., with .env)

Quickstart (read‑only)

from py_clob_client.client import ClobClient

client = ClobClient("https://clob.polymarket.com")  # Level 0 (no auth)

ok = client.get_ok()
time = client.get_server_time()
print(ok, time)

Start trading (EOA)

Note: If using MetaMask or hardware wallet, you must first set token allowances. See Token Allowances section below.

from py_clob_client.client import ClobClient

HOST = "https://clob.polymarket.com"
CHAIN_ID = 137
PRIVATE_KEY = "<your-private-key>"
FUNDER = "<your-funder-address>"

client = ClobClient(
    HOST,  # The CLOB API endpoint
    key=PRIVATE_KEY,  # Your wallet's private key
    chain_id=CHAIN_ID,  # Polygon chain ID (137)
    signature_type=1,  # 1 for email/Magic wallet signatures
    funder=FUNDER  # Address that holds your funds
)
client.set_api_creds(client.create_or_derive_api_creds())

Start trading (proxy wallet)

For email/Magic or browser wallet proxies, you need to specify two additional parameters:

Funder Address

The funder address is the actual address that holds your funds on Polymarket. When using proxy wallets (email wallets like Magic or browser extension wallets), the signing key differs from the address holding the funds. The funder address ensures orders are properly attributed to your funded account.

Signature Types

The signature_type parameter tells the system how to verify your signatures:

• signature_type=0 (default): Standard EOA (Externally Owned Account) signatures - includes MetaMask, hardware wallets, and any wallet where you control the private key directly
• signature_type=1: Email/Magic wallet signatures (delegated signing)
• signature_type=2: Browser wallet proxy signatures (when using a proxy contract, not direct wallet connections)

from py_clob_client.client import ClobClient

HOST = "https://clob.polymarket.com"
CHAIN_ID = 137
PRIVATE_KEY = "<your-private-key>"
PROXY_FUNDER = "<your-proxy-or-smart-wallet-address>"  # Address that holds your funds

client = ClobClient(
    HOST,  # The CLOB API endpoint
    key=PRIVATE_KEY,  # Your wallet's private key
    chain_id=CHAIN_ID,  # Polygon chain ID (137)
    signature_type=1,  # 1 for email/Magic wallet signatures
    funder=PROXY_FUNDER  # Address that holds your funds
)
client.set_api_creds(client.create_or_derive_api_creds())

Find markets, prices, and orderbooks

from py_clob_client.client import ClobClient
from py_clob_client.clob_types import BookParams

client = ClobClient("https://clob.polymarket.com")  # read-only

token_id = "<token-id>"  # Get a token ID: https://docs.polymarket.com/developers/gamma-markets-api/get-markets

mid = client.get_midpoint(token_id)
price = client.get_price(token_id, side="BUY")
book = client.get_order_book(token_id)
books = client.get_order_books([BookParams(token_id=token_id)])
print(mid, price, book.market, len(books))

Place a market order (buy by $ amount)

Note: EOA/MetaMask users must set token allowances before trading. See Token Allowances section below.

from py_clob_client.client import ClobClient
from py_clob_client.clob_types import MarketOrderArgs, OrderType
from py_clob_client.order_builder.constants import BUY

HOST = "https://clob.polymarket.com"
CHAIN_ID = 137
PRIVATE_KEY = "<your-private-key>"
FUNDER = "<your-funder-address>"

client = ClobClient(
    HOST,  # The CLOB API endpoint
    key=PRIVATE_KEY,  # Your wallet's private key
    chain_id=CHAIN_ID,  # Polygon chain ID (137)
    signature_type=1,  # 1 for email/Magic wallet signatures
    funder=FUNDER  # Address that holds your funds
)
client.set_api_creds(client.create_or_derive_api_creds())

mo = MarketOrderArgs(token_id="<token-id>", amount=25.0, side=BUY, order_type=OrderType.FOK)  # Get a token ID: https://docs.polymarket.com/developers/gamma-markets-api/get-markets
signed = client.create_market_order(mo)
resp = client.post_order(signed, OrderType.FOK)
print(resp)

Place a limit order (shares at a price)

Note: EOA/MetaMask users must set token allowances before trading. See Token Allowances section below.

from py_clob_client.client import ClobClient
from py_clob_client.clob_types import OrderArgs, OrderType
from py_clob_client.order_builder.constants import BUY

HOST = "https://clob.polymarket.com"
CHAIN_ID = 137
PRIVATE_KEY = "<your-private-key>"
FUNDER = "<your-funder-address>"

client = ClobClient(
    HOST,  # The CLOB API endpoint
    key=PRIVATE_KEY,  # Your wallet's private key
    chain_id=CHAIN_ID,  # Polygon chain ID (137)
    signature_type=1,  # 1 for email/Magic wallet signatures
    funder=FUNDER  # Address that holds your funds
)
client.set_api_creds(client.create_or_derive_api_creds())

order = OrderArgs(token_id="<token-id>", price=0.01, size=5.0, side=BUY)  # Get a token ID: https://docs.polymarket.com/developers/gamma-markets-api/get-markets
signed = client.create_order(order)
resp = client.post_order(signed, OrderType.GTC)
print(resp)

Manage orders

Note: EOA/MetaMask users must set token allowances before trading. See Token Allowances section below.

from py_clob_client.client import ClobClient
from py_clob_client.clob_types import OpenOrderParams

HOST = "https://clob.polymarket.com"
CHAIN_ID = 137
PRIVATE_KEY = "<your-private-key>"
FUNDER = "<your-funder-address>"

client = ClobClient(
    HOST,  # The CLOB API endpoint
    key=PRIVATE_KEY,  # Your wallet's private key
    chain_id=CHAIN_ID,  # Polygon chain ID (137)
    signature_type=1,  # 1 for email/Magic wallet signatures
    funder=FUNDER  # Address that holds your funds
)
client.set_api_creds(client.create_or_derive_api_creds())

open_orders = client.get_orders(OpenOrderParams())

order_id = open_orders[0]["id"] if open_orders else None
if order_id:
    client.cancel(order_id)

client.cancel_all()

Markets (read‑only)

from py_clob_client.client import ClobClient

client = ClobClient("https://clob.polymarket.com")
markets = client.get_simplified_markets()
print(markets["data"][:1])

User trades (requires auth)

Note: EOA/MetaMask users must set token allowances before trading. See Token Allowances section below.

from py_clob_client.client import ClobClient

HOST = "https://clob.polymarket.com"
CHAIN_ID = 137
PRIVATE_KEY = "<your-private-key>"
FUNDER = "<your-funder-address>"

client = ClobClient(
    HOST,  # The CLOB API endpoint
    key=PRIVATE_KEY,  # Your wallet's private key
    chain_id=CHAIN_ID,  # Polygon chain ID (137)
    signature_type=1,  # 1 for email/Magic wallet signatures
    funder=FUNDER  # Address that holds your funds
)
client.set_api_creds(client.create_or_derive_api_creds())

last = client.get_last_trade_price("<token-id>")
trades = client.get_trades()
print(last, len(trades))

Important: Token Allowances for MetaMask/EOA Users

Do I need to set allowances?

• Using email/Magic wallet? No action needed - allowances are set automatically.
• Using MetaMask or hardware wallet? You need to set allowances before trading.

What are allowances?

Think of allowances as permissions. Before Polymarket can move your funds to execute trades, you need to give the exchange contracts permission to access your USDC and conditional tokens.

Quick Setup

You need to approve two types of tokens:

1. USDC (for deposits and trading)
2. Conditional Tokens (the outcome tokens you trade)

Each needs approval for the exchange contracts to work properly.

Setting Allowances

Here's a simple breakdown of what needs to be approved:

For USDC (your trading currency):

• Token: 0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174
• Approve for these contracts:
  • 0x4bFb41d5B3570DeFd03C39a9A4D8dE6Bd8B8982E (Main exchange)
  • 0xC5d563A36AE78145C45a50134d48A1215220f80a (Neg risk markets)
  • 0xd91E80cF2E7be2e162c6513ceD06f1dD0dA35296 (Neg risk adapter)

For Conditional Tokens (your outcome tokens):

• Token: 0x4D97DCd97eC945f40cF65F87097ACe5EA0476045
• Approve for the same three contracts above

Example Code

See this Python example for setting allowances programmatically.

Pro tip: You only need to set these once per wallet. After that, you can trade freely.

Notes

• To discover token IDs, use the Markets API Explorer: Get Markets.
• Prices are in dollars from 0.00 to 1.00. Shares are whole or fractional units of the outcome token.

See /example for more.