EventGraph
EventGraph API v1 is now live

The intelligence layer for prediction markets

Unified prediction market data across venues — real-time prices, cross-venue intelligence, and developer APIs built for traders, developers, and AI agents.

Aggregating data from the world's leading prediction markets

PolymarketKalshiLimitlessOpinion Trade

EventGraph Terminal

Explore prediction markets across venues with unified data and analytics.

app.eventgraph.ai/terminal
The Problem

Prediction Market Data Is Fragmented Across Venues

Prediction markets are spread across multiple platforms with inconsistent data formats and disconnected APIs.

  • Markets cannot be compared across venues
  • No unified probability consensus
  • Developers must integrate multiple APIs

Manual venue monitoring simply doesn't scale.

EventGraph aggregates, normalizes, and analyzes prediction markets across platforms to create a unified intelligence layer.

How EventGraph Works

Supported Venues

Polymarket
Kalshi
Limitless
Opinion Trade
+ More

Normalization Engine

Normalization & Data Pipeline

EventGraph Intelligence Engine

EventGraph Intelligence Layer

Cross-Venue IntelligenceProbability ConsensusArbitrage Detection

Build With EventGraph

REST APIs
Terminal
AI Agents (MCP)

Everything you need to build on prediction markets

One platform for normalized data, cross-venue intelligence, and developer tooling across major prediction markets.

8,000+

Events tracked

20,000+

Markets indexed

$7B+

Historical volume

4+

Venues integrated

Market Data

Unified prediction market data — events, markets, prices, trades, and liquidity across venues via a normalized schema.

Market Intelligence

Cross-venue intelligence for prediction markets — compare prices, detect arbitrage opportunities, and analyze probability consensus across venues.

Developer & AI Platform

Developer-first APIs and structured datasets with MCP support, enabling developers and AI agents to build on prediction market intelligence.

Terminal

The EventGraph Terminal

Professional tools for exploring prediction markets across venues.

  • Explore thousands of prediction markets across venues
  • Compare odds and probabilities across platforms
  • Detect real-time cross-venue arbitrage opportunities
  • Build custom alerts and analytics dashboards

Monitor, compare, and analyze markets across venues in one place.

Markets
app.eventgraph.ai/terminal/markets

Explore prediction markets across venues with unified event data.

EventProbVolume
US Election 202662%$2.4M
Fed Rate Cut Jul38%$890K
SpaceX Mars 202742%$1.1M
AI Regulation Bill71%$560K
BTC $150K EOY55%$3.2M
Trump VP Pick81%$1.8M
Showing 6 of 48+ resultsUpdated 2s ago
Request
curl https://api.eventgraph.ai/v1/events/evt_2028_us_president \
  -H "Authorization: Bearer YOUR_API_KEY"
Response
{
  "event": "2028 US Presidential Election Winner",
  "consensus_probability": 0.54,
  "arbitrage_spread": 0.04,
  "last_updated": "2026-03-06T16:30:00Z",
  "venues": [
    { "name": "polymarket", "price": 0.56 },
    { "name": "kalshi", "price": 0.52 }
  ]
}
bash•live
Developer APIs

Build with the EventGraph API

We normalize fragmented prediction market data so you can build faster.

Used by traders, developers, and AI agents to build prediction market applications.

REST JSON API  •  Real-time market data  •  99.9% uptime

Data from

PolymarketKalshiLimitlessOpinionTrade
Unified REST endpoints
Normalized event schemas
Cross-venue queries
Arbitrage detection
AI Native Infrastructure

Prediction Market Data for AI Agents

Let AI agents query prediction markets, compare venues, and analyze probabilities using MCP.

AI agents can use EventGraph to analyze prediction markets, detect arbitrage opportunities, and summarize probability consensus across venues.

OpenAIClaudeLangChainCursor
↓

EventGraph

MCP + Data Engine

Normalization · Intelligence · Arbitrage

↓
PolymarketKalshiLimitlessOpinionTrade

MCP Functions

›eventgraph.get_events()
›eventgraph.get_cross_venue_prices()
›eventgraph.detect_arbitrage()
›eventgraph.get_consensus_probability()

Works with

OpenAIClaudeLangChainOpenClawAgentBotCursor

Pricing

Start free, scale as you grow

No credit card required. Upgrade when you need more.

Free

$0/mo

For exploration and prototyping

  • 100K API calls / month
  • All basic endpoints
  • Market search & discovery
  • Community support

Pro

Popular
$29/mo

For developers and trading apps

  • 1M API calls / month
  • Cross-venue analytics
  • Arbitrage detection
  • Priority support

Enterprise

Custom

For teams with advanced needs

  • 10M+ API calls
  • Historical datasets
  • WebSocket streaming
  • Dedicated support & SLA
Compare all features →

Insights

Latest from the team

Market analysis, technical deep dives, and product updates.

Market Analysis

Market Analysis

Polymarket vs Kalshi: A Deep Dive into Liquidity

Comparing order book depth, spread dynamics, and execution quality across the two largest prediction market venues.

Mar 4, 2026·8 min read
Developer

Building AI Agents That Trade Prediction Markets Using MCP

A step-by-step guide to connecting AI agents to live prediction market data through EventGraph's MCP server.

Feb 28, 2026·12 min read
Trading Strategy

Arbitrage in Election Markets: Patterns, Risks, and Returns

How cross-venue price discrepancies create opportunities — and the real-world constraints traders face capturing them.

Feb 20, 2026·10 min read
View all posts →

FAQ

Common questions

What makes EventGraph different from individual venue APIs?

Prediction market data is fragmented across platforms with incompatible schemas. EventGraph normalizes everything into a single API — compare probabilities, detect arbitrage, and build on a unified dataset instead of integrating each venue separately.

Can I use EventGraph with AI agents?

Yes. EventGraph ships an MCP server (Model Context Protocol) so AI agents can query prediction markets directly. Works with OpenAI, Claude, LangChain, and other agent frameworks out of the box.

How quickly can I integrate?

Most developers are making their first API call within minutes. The REST API uses simple GET endpoints with JSON responses — no SDKs required, though we provide client libraries for Python and TypeScript.

Is there a free tier?

Yes. The free plan includes generous API limits so you can explore the data, prototype applications, and validate your use case before upgrading. No credit card required.

Which prediction markets are supported?

EventGraph aggregates data from Polymarket, Kalshi, Limitless, and OpinionTrade — covering thousands of active markets. We continuously add new venues to the index.