1. Get Your API Key
Sign up for free at dashboard.predexon.com — no credit card required.
2. Make Your First Request
Set up your environment
All API requests go to https://api.predexon.com with your API key in the x-api-key header.export PREDEXON_API_KEY="your_api_key"
Fetch top markets
Get the highest-volume open markets on Polymarket:curl -H "x-api-key: $PREDEXON_API_KEY" \
"https://api.predexon.com/v2/polymarket/markets?status=open&sort=volume&limit=5"
Explore the response
{
"markets": [
{
"condition_id": "0x1234...",
"market_slug": "will-donald-trump-win-the-2024-us-presidential-election",
"title": "Will Trump win the 2024 election?",
"status": "open",
"outcomes": [
{"label": "Yes", "token_id": "123...", "price": 0.62},
{"label": "No", "token_id": "456...", "price": 0.38}
],
"total_volume_usd": 1500000000,
"liquidity_usd": 25000000
}
],
"pagination": { "limit": 5, "offset": 0, "total": 1234, "has_more": true }
}
3. Try More Endpoints
Price History
Wallet Positions
Cross-Platform Matches
WebSocket
Fetch OHLCV candlestick data for charting:response = requests.get(
f"{BASE_URL}/v2/polymarket/candlesticks/{condition_id}",
headers=HEADERS,
params={"interval": 60, "start_time": 1704067200, "end_time": 1704153600}
)
Get all open positions for a wallet:response = requests.get(
f"{BASE_URL}/v2/polymarket/wallet/positions/{wallet_address}",
headers=HEADERS,
params={"sort_by": "value", "limit": 50}
)
Find equivalent markets on Kalshi:response = requests.get(
f"{BASE_URL}/v2/matching-markets",
headers=HEADERS,
params={"polymarket_market_slug": "will-trump-win-2024"}
)
Stream live trades in real time:const ws = new WebSocket('wss://wss.predexon.com/v1/YOUR_API_KEY');
ws.onopen = () => ws.send(JSON.stringify({
action: 'subscribe',
platform: 'polymarket',
version: 1,
type: 'orders',
filters: { users: ['0x1234...'] }
}));
ws.onmessage = (e) => console.log(JSON.parse(e.data));
Plans & Rate Limits
Most data is free. Core market data, trades, orderbooks, and pricing endpoints are free and unlimited on all plans.
| Tier | Rate Limit | Monthly Requests | Price |
|---|
| Free | 1 req/sec | 1,000 | $0/month |
| Dev | 20 req/sec | 1,000,000 | $49/month |
| Pro | 100 req/sec | 5,000,000 | $249/month |
| Enterprise | Custom | Unlimited | $499+/month |
Free tier excludes smart wallet, market matching, and WebSocket. See predexon.com/pricing for details. Error Handling
| Code | Description |
|---|
200 | Success |
400 | Bad request — check your parameters |
403 | Invalid or missing API key |
429 | Rate limit exceeded — implement exponential backoff |
500 | Internal server error |
{
"error": "Invalid filter combination",
"message": "Only one of market_slug, token_id, or condition_id can be provided"
}
Next Steps
API Reference
Explore all endpoints with interactive playground.
WebSocket
Stream real-time events.
Trading API
Place orders programmatically.
