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"
import requests
BASE_URL = "https://api.predexon.com"
API_KEY = "your_api_key"
HEADERS = { "x-api-key" : API_KEY }
const BASE_URL = "https://api.predexon.com" ;
const HEADERS = { "x-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"
response = requests.get(
f " { BASE_URL } /v2/polymarket/markets" ,
headers = HEADERS ,
params = { "status" : "open" , "sort" : "volume" , "limit" : 5 }
)
for market in response.json()[ "markets" ]:
print ( f " { market[ 'title' ] } : $ { market[ 'total_volume_usd' ] :,.0f} volume" )
const response = await fetch (
` ${ BASE_URL } /v2/polymarket/markets?status=open&sort=volume&limit=5` ,
{ headers: HEADERS }
);
const { markets } = await response . json ();
markets . forEach ( m =>
console . log ( ` ${ m . title } : $ ${ m . total_volume_usd . toLocaleString () } volume` )
);
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 200Success 400Bad request - check your parameters 403Invalid or missing API key 429Rate limit exceeded - implement exponential backoff 500Internal server error
{
"error" : "Invalid filter combination" ,
"message" : "Only one of market_slug, token_id, or condition_id can be provided"
}
Next Steps
Data & Signals Explore every endpoint with interactive playground.
WebSocket Stream real-time events.
Unified Execution Infra Place orders across every venue.