This guide walks you through placing your first trade on a prediction market using the Predexon Trading API.
Prerequisites
Request your private beta API key on Discord before starting. Step 1: Create a User
Create a user to get managed wallet addresses for depositing funds.
curl -X POST \
-H "x-api-key: YOUR_API_KEY" \
"https://trade.predexon.com/api/users/create"
{
"userId": "550e8400-e29b-41d4-a716-446655440000",
"polymarketWalletAddress": "0x1234...5678",
"kalshiWalletAddress": "7BfknMUrXjZ..."
}
Save the userId - you’ll need it for all subsequent API calls.
Step 2: Fund Your Wallet
Send tokens to the wallet address for the venue you want to trade on.
Send USDC.e on Polygon to your polymarketWalletAddress.| Token | Chain | Contract Address |
|---|
| USDC.e | Polygon (137) | 0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174 |
You can also use the Bridge API to deposit from other chains (Ethereum, Solana, Bitcoin). Send both USDC and SOL on Solana to your kalshiWalletAddress.| Token | Purpose | Contract Address |
|---|
| USDC | Trading funds | EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v |
| SOL | Gas for transactions | Native token |
Kalshi trades require SOL for Solana transaction fees. We recommend sending at least 0.05 SOL to cover multiple trades.
Step 3: Find a Market
Use the Data API to find a market you want to trade.
Get markets from the List Markets endpoint:curl -H "x-api-key: YOUR_API_KEY" \
"https://api.predexon.com/v1/markets?status=active&sort=volume&limit=5"
tokenId in the outcomes array for the side you want to trade:{
"markets": [{
"question": "Will Bitcoin reach $100k?",
"outcomes": [
{ "label": "Yes", "tokenId": "71321045679252..." },
{ "label": "No", "tokenId": "48331043336612..." }
]
}]
}
Get markets from the Kalshi List Markets endpoint:curl -H "x-api-key: YOUR_API_KEY" \
"https://api.predexon.com/v1/kalshi/markets?status=open&sort=volume&limit=5"
ticker field with outcome set to "Yes" or "No":{
"markets": [{
"ticker": "KXBTC-25JAN10-B100000",
"title": "Bitcoin above $100,000?"
}]
}
Step 4: Place an Order
Now place your first trade.
import requests
user_id = "YOUR_USER_ID"
# Place a limit order to buy "Yes" shares at $0.65
response = requests.post(
f"https://trade.predexon.com/api/users/{user_id}/orders",
headers={
"x-api-key": "YOUR_API_KEY",
"Content-Type": "application/json"
},
json={
"venue": "polymarket",
"tokenId": "71321045679252...", # From Step 3
"side": "buy",
"amount": "10.00", # Spend $10 USDC
"price": "0.65",
"type": "limit"
}
)
order = response.json()
print(f"Order placed: {order['orderId']}")
print(f"Status: {order['status']}")
Limit orders sit on the orderbook until matched. Use "type": "market" for immediate execution at best available price.
import requests
user_id = "YOUR_USER_ID"
# Buy "Yes" on a Kalshi market
response = requests.post(
f"https://trade.predexon.com/api/users/{user_id}/orders",
headers={
"x-api-key": "YOUR_API_KEY",
"Content-Type": "application/json"
},
json={
"venue": "kalshi",
"ticker": "KXBTC-25JAN10-B100000", # From Step 3
"outcome": "Yes",
"side": "buy",
"amount": "10.00" # Spend $10 USDC
}
)
order = response.json()
print(f"Order filled: {order['orderId']}")
print(f"Price: {order['price']}")
Kalshi orders execute instantly as atomic swaps - no orderbook, no waiting.
Step 5: Check Your Position
View your positions to see your holdings and P&L.
response = requests.get(
f"https://trade.predexon.com/api/users/{user_id}/positions",
headers={"x-api-key": "YOUR_API_KEY"}
)
positions = response.json()["positions"]
for pos in positions:
print(f"{pos['title']} - {pos['outcome']}")
print(f" Shares: {pos['size']} @ avg ${pos['averagePrice']}")
print(f" Current value: ${pos['currentValue']}")
print(f" P&L: ${pos['pnl']}")
Next Steps
Complete Example
Here’s a full Python script to place your first trade:
import requests
API_KEY = "YOUR_API_KEY"
BASE_URL = "https://trade.predexon.com"
DATA_URL = "https://api.predexon.com"
HEADERS = {"x-api-key": API_KEY, "Content-Type": "application/json"}
# 1. Create user
user = requests.post(f"{BASE_URL}/api/users/create", headers=HEADERS).json()
user_id = user["userId"]
print(f"Created user: {user_id}")
print(f"Fund Polymarket wallet: {user['polymarketWalletAddress']}")
# 2. (Manual step) Send USDC.e to the Polymarket wallet address
# 3. Get a market
markets = requests.get(
f"{DATA_URL}/v1/markets",
headers=HEADERS,
params={"status": "active", "sort": "volume", "limit": 1}
).json()
market = markets["markets"][0]
tokenId = market["outcomes"][0]["tokenId"] # Buy "Yes" side
print(f"Trading: {market['question']}")
# 4. Check balance
balance = requests.get(
f"{BASE_URL}/api/users/{user_id}/balance",
headers=HEADERS
).json()
print(f"Available balance: ${balance['balances'][0]['available']}")
# 5. Place order
order = requests.post(
f"{BASE_URL}/api/users/{user_id}/orders",
headers=HEADERS,
json={
"venue": "polymarket",
"tokenId": tokenId,
"side": "buy",
"amount": "5.00",
"price": "0.50",
"type": "limit"
}
).json()
print(f"Order placed: {order['orderId']} - {order['status']}")
# 6. Check positions
positions = requests.get(
f"{BASE_URL}/api/users/{user_id}/positions",
headers=HEADERS
).json()
print(f"Total positions: {len(positions['positions'])}")
