Best brokers with Python API for CFD & spread betting

Which API Should a Python Beginner Start With?

Capital.com if you want the absolute simplest start. IG if you want something you won’t outgrow in six months.

Capital.com’s API requires only the requests library and basic HTTP knowledge. You can authenticate and pull prices in 10 lines of code. It’s ideal for learning REST concepts and building confidence before tackling streaming data or complex authentication.

IG’s API is a better long-term investment. The trading_ig library handles authentication and streaming for you, the documentation is thorough, and you have access to 17,000+ markets. The learning curve is steeper than Capital.com but shallower than IBKR. Most Python trading developers I know started with IG and never needed to switch.

For broader context on automated trading approaches, see our guides on building a trading bot and AI trading robots. For MT4-specific automation, read our Expert Advisors guide.

Working Python Code Example – IG API Authentication & Price Pull

This script authenticates with IG’s REST API, pulls the current GBP/USD price, and prints it. It runs on Python 3.8+ with only the requests library (no trading_ig required). Replace the placeholder credentials with your IG demo account details.

import requests

# IG Demo API credentials (replace with your own)
API_KEY = "your-api-key-here"
USERNAME = "your-username"
PASSWORD = "your-password"

# Authentication
session = requests.Session()
session.headers.update({
    "X-IG-API-KEY": API_KEY,
    "Content-Type": "application/json; charset=UTF-8",
    "Accept": "application/json; charset=UTF-8",
    "Version": "2"
})

auth_payload = {
    "identifier": USERNAME,
    "password": PASSWORD
}

auth_url = "https://demo-api.ig.com/gateway/deal/session"
auth_response = session.post(auth_url, json=auth_payload)

if auth_response.status_code != 200:
    print(f"Auth failed: {auth_response.status_code}")
    exit()

# Extract tokens from response headers
cst = auth_response.headers.get("CST")
x_security_token = auth_response.headers.get("X-SECURITY-TOKEN")

session.headers.update({
    "CST": cst,
    "X-SECURITY-TOKEN": x_security_token
})

print("Authenticated successfully.")

# Pull GBP/USD price
market_url = "https://demo-api.ig.com/gateway/deal/markets/CS.D.GBPUSD.TODAY.IP"
market_response = session.get(market_url)
market_data = market_response.json()

bid = market_data["snapshot"]["bid"]
offer = market_data["snapshot"]["offer"]
spread = round(offer - bid, 4)

print(f"GBP/USD - Bid: {bid}, Offer: {offer}, Spread: {spread}")

# Clean up session
session.delete(auth_url)
print("Session closed.")

This is a starting point, not a production system. For live trading, you would add error handling, rate-limit management, and the Lightstreamer connection for real-time price streaming. The trading_ig library handles all of this automatically if you prefer a higher-level interface.

Frequently Asked Questions

References

1. IG REST API Documentation – labs.ig.com/rest-trading-api-reference
2. Capital.com API Documentation – open-api.capital.com
3. Interactive Brokers API Guide – interactivebrokers.github.io/tws-api
4. FCA Financial Services Register – register.fca.org.uk
5. trading_ig Python Library – github.com/ig-python/trading-ig