Polygon.io

Stocks, options, forex, and crypto market data over REST and WebSocket, with a free self-serve API key

Interfaces

1/5 verified

Verified means we fetched it and it answered. Claimed means it is listed but has not been reached yet.

Related services
Hyperliquid Permissionless perpetuals exchange whose full order book and order-entry API are open to any wallet-signed client	4/5
Alpaca Commission-free US stocks, options, and crypto brokerage API with a free paper-trading environment	4/5
Polymarket Onchain prediction market with an open CLOB API and wallet-signed order placement	4/5
Manifold Play-money prediction market with a fully open API that explicitly invites trading bots	4/5
The Odds API Live and historical sports odds from global bookmakers over a REST API with a free self-serve tier	4/5
Kalshi CFTC-regulated event contract exchange with a documented REST and WebSocket API for algorithmic trading	4/5