Matching Markets
Find equivalent markets across all supported prediction market platforms using a free-text query, Polymarket slug, or Kalshi ticker.
/v2/matching-marketsQuery Parameters
Free-text search query (e.g. 'federal reserve rate'). Provide exactly one of q, polymarket_key, or kalshi_key.
Polymarket slug or identifier.
Kalshi ticker.
Response Schema
Whether matching events were found.
Number of matching events returned.
Matched events with cross-platform market groups.
Event name (e.g. "Will the Fed cut rates in March 2026?").
Category: economics, sports, election, etc.
Date of the event.
Match confidence: "high" or "medium". Low-confidence events are excluded.
Market groups within this event.
Group title (e.g. the specific proposition).
Matched markets across platforms.
Platform (polymarket, kalshi, etc.).
Direct link to the market.
Platform-specific market identifier.
Authentication
API Key
To secure your requests, we strongly recommend passing your API key via the X-API-Key header. This prevents sensitive keys from being exposed in access logs or browser history.
X-API-Key: pmx_test_5e8f...Rate Limits
API rate limits are enforced based on the tier associated with your API key. Limits are tracked on two dimensions: requests per second and requests per month. Each completed request counts toward the global monthly quota. Separate endpoint-group monthly limits (matched markets, arbitrage, EV) only advance when the response body has success: true.
Usage is returned on responses via headers such as:
X-RateLimit-Limit-Second: 10X-RateLimit-Remaining-Second: 9X-RateLimit-Limit-Month: 1000X-RateLimit-Remaining-Month: 842Example (endpoint-group, when applicable)X-RateLimit-Limit-Arb-Month: 500X-RateLimit-Remaining-Arb-Month: 412If you exceed a rate limit, the API returns a 429 status with a Retry-After header indicating when you can resume.
Request
Live API Key
Search Parameters
Response
Enter an API key and click "Try it now" to see the live response data.