One API forEvery Prediction Market
Stop juggling 3 APIs. Get unified data from Polymarket, Kalshi & Gemini in a single call. Ship faster with our comprehensive API documentation and transparent pricing.
Will Iran nuclear deal be reached by March 2026?
Fed rate cut at next FOMC meeting?
Supreme Court rule on crypto regulation in 2026?
Will Iran nuclear deal be reached by March 2026?
Fed rate cut at next FOMC meeting?
Supreme Court rule on crypto regulation in 2026?
Why waste time on integration?
Stop building the same API adapter three times. We handle the complexity so you can focus on what matters.
Without Propheseer
- 3 separate APIs
- 3 auth systems
- 3 data formats
- Manual arbitrage hunting
- Hours of integration
With Propheseer
- 1 unified API
- 1 API key
- Normalized JSON
- Auto opportunity detection
- 5 minutes to first call
Ship faster with Official SDKs
Type-safe clients for TypeScript and Python. Install, import, and start querying prediction markets in minutes.
// Install the SDK npm install propheseer // Connect to prediction markets import Propheseer from 'propheseer' const client = new Propheseer({ apiKey: process.env.PROPHESEER_API_KEY }) // Fetch markets from all platforms const page = await client.markets.list({ source: 'polymarket', category: 'politics' }) console.log(page.data)
Built for Developers
One SDK for every prediction market. Our official TypeScript and Python clients give you type-safe access to Polymarket, Kalshi, and Gemini with a unified interface.
- Full type safety and autocomplete
- Automatic retries with exponential backoff
- Built-in pagination helpers
- Normalized data across all platforms
Data from the best sources
We aggregate and normalize data from the leading prediction market platforms.
Polymarket
Crypto-native prediction markets
Kalshi
CFTC-regulated exchange
Gemini
Gemini prediction markets
See it in action
Simple REST API. Clean JSON responses. Try it yourself.
/v1/markets?category=politics&limit=3{
"data": [
{
"id": "pm_trump_2028",
"source": "polymarket",
"question": "Will Trump win 2028?",
"category": "politics",
"status": "open",
"outcomes": [
{ "name": "Yes", "probability": 0.52 },
{ "name": "No", "probability": 0.48 }
],
"url": "https://polymarket.com/event/..."
},
{
"id": "ks_fed_rate_jan",
"source": "kalshi",
"question": "Will the Fed cut rates in January?",
"category": "finance",
"status": "open",
"outcomes": [
{ "name": "Yes", "probability": 0.35 },
{ "name": "No", "probability": 0.65 }
],
"url": "https://kalshi.com/markets/..."
},
{
"id": "gm_btc_100k",
"source": "gemini",
"question": "Will BTC be above $100K on Dec 31?",
"category": "finance",
"status": "open",
"outcomes": [
{ "name": "Yes", "probability": 0.68 },
{ "name": "No", "probability": 0.32 }
],
"url": "https://exchange.gemini.com/prediction-markets/..."
}
],
"meta": { "total": 2533, "limit": 3 }
}Built for your use case
Whether you're building trading tools, research platforms, or media products.
Arbitrage Detection
Find price gaps across platforms. Buy low on one, sell high on another.
Trading Bots
Automate trades based on market movements and probability changes.
News & Media
Embed live prediction odds in articles. Show readers what markets think.
Research
Track prediction market accuracy. Analyze forecasting performance.
Simple, transparent pricing
Start free. Upgrade when you need more. No hidden fees.
Free
Perfect for trying out the API and hobby projects
- API Requests: 100/day
- Rate Limit: 10 req/min
- Unusual Trade DetectionNewUpgrade to Pro
- WebSocket Streaming: —
- Arbitrage Detection: —
Pro
or $16.66/mo billed annually
For serious traders and developers building applications
- API Requests: 10,000/day
- Rate Limit: 100 req/min
- Unusual Trade DetectionNewWhale & anomaly alerts
- WebSocket Streaming: 50 markets
- Arbitrage Detection: Included
Business
Includes all of Pro, with custom integrations tailored to your needs
- API Requests: 100,000/day
- Rate Limit: 1,000 req/min
- Unusual Trade DetectionNewWhale & anomaly alerts
- WebSocket Streaming: Unlimited
- Arbitrage Detection: Included
Ready to aggregate
prediction markets?
Get your free API key in 30 seconds. No credit card required. Start building with our API documentation.
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