Massive (formerly Polygon.io)
US stock, options, forex and crypto market data API; polygon.io now redirects to massive.com.
A developer favourite for US market data, with a free tier to start and real-time on the top stocks plan.
Who it is for
Developers building bots or dashboards on US stocks who need clean historical and live data.
Strengths
- Free Basic plan: 5 API calls per minute, 2 years of history, end-of-day data.
- Paid stocks plans with unlimited API calls and 5 to 20+ years of history.
Good to know
- Starter and Developer stocks plans are 15-minute delayed; real-time requires Advanced.
- polygon.io URLs now redirect to massive.com; older tutorials use the old name.
Want a bot built on Massive (formerly Polygon.io), or something similar?
We set it up, connect it to your accounts and keep it running.
Real-life uses
Earnings and gap scanner
🔥 High demandPre-market list of stocks gapping on earnings or news that match your filters.
Correlation and regime dashboard
Rolling correlations, volatility regimes and trend state across the assets you trade.
Sources
Every fact on this page comes from these sources, checked on 2026-10-24. If something has changed, the source wins; tell us at contact@tradebotcheck.com.
- https://massive.com/pricing: stocks plans, prices, limits, delays
- https://polygon.io/pricing: permanent redirect (301) to massive.com/pricing
Alternatives in Market data
Alpha Vantage
Market data API for stocks, forex, crypto and technical indicators, with a free tier and per-minute premium plans.
CoinGecko API
Crypto data API (prices, market cap, history) with a free Demo plan.
EODHD
Global financial data API (end-of-day, intraday, fundamentals, news) covering stocks, ETFs, forex and crypto from many exchanges.
Tiingo
Affordable financial data API with 30+ years of end-of-day prices on 110,000+ securities, fundamentals, crypto and news.