Massive (formerly Polygon.io)
by Massive (Polygon.io, Inc.) · API service · also known as Polygon.io, Polygon, Massive.com
Market data platform (renamed from Polygon.io in October 2025) with REST and WebSocket APIs, flat files and SQL access for US stocks, options, indices, forex, crypto and futures
Overview
Massive is the market data company formerly known as Polygon.io; the rename took effect on 30 October 2025 with polygon.io redirecting to massive.com and a new api.massive.com base running alongside the legacy api.polygon.io endpoints, which the company plans to phase out after notice. It provides real-time and historical data for US stocks (including dark-pool and OTC prints), options chains with Greeks and implied volatility, global indices, forex and crypto, and futures from the CME Group exchanges.
Access methods are REST APIs for queries and history (aggregate bars, trades, quotes, snapshots, reference tickers, corporate actions, technical indicators, fundamentals and EDGAR-derived filings sections), WebSocket streams for live data, bulk flat files of historical data through an S3-compatible interface, SQL access on request and an MCP server for AI tools; official client libraries exist for Python, JavaScript, Go and Java, and migration guides map endpoints from other vendors. Pricing is per asset class with separate individual and business tiers, monthly or annual billing, add-on datasets and partner data; individual plans are restricted to personal use under the Massive for Individuals terms.
Researchers choose it for API-first access to tick-level US equity and options history; constraints are the vendor-locked SDKs during the rename transition, usage terms that distinguish individual from business use, and the need for business licences for redistribution or commercial applications.
Editorial note on uncertainty. Slug retained as polygon-io for cross-linking; the product's current name is Massive. A free tier was not visible on the pricing page at check time.
Capabilities
- REST APIs for bars, trades, quotes, snapshots and reference data
- WebSocket streaming for stocks, options, futures, indices, forex and crypto
- Flat-file bulk history via S3-compatible storage
- Options chains with Greeks and implied volatility
- Fundamentals, corporate actions and EDGAR-derived filing sections
- Official SDKs for Python, JavaScript, Go and Java
- MCP server for AI assistants
- SQL access on request
Typical workflows
- Downloading full-day trade files for microstructure research
- Streaming quotes into a live dashboard
- Backfilling a minute-bar database via REST aggregates
Strengths
- API-first with multiple delivery methods
- Tick-level US equities and options history
- Official SDKs and migration guides
Limitations
- Rename in progress: legacy polygon.io endpoints to be retired
- Individual plans limited to personal use
- Subscription required; coverage centred on US markets
Prerequisites
- Account and API key
- Subscription for the relevant asset class
Who it is for
- Quant developers and researchers
- Fintech application builders
Alternatives & comparison
Databento prices historical data by usage and exposes full order-book schemas; FirstRate Data sells downloadable bundles under a perpetual licence; Alpha Vantage is a free-tier-first REST API; yfinance scrapes Yahoo without a licence. Massive sits in the subscription-API tier with flat files and streaming.
- Alpha Vantage
REST API for stock, ETF, options, forex, crypto, commodity and economic data plus fundamentals, news sentiment and technical indicators, with a free key tier and premium plans
ProprietaryFreemium - Bloomberg Terminal
Bloomberg's subscription workstation for market data, news, analytics, messaging and execution, with Excel integration and the BLPAPI library for C++, Java, .NET and Python
ProprietaryPaid - Databento
Usage-priced market data platform with normalized order-book (MBO/MBP), trades, OHLCV and reference schemas for futures, options and equities, delivered via historical, live and batch APIs in the DBN format
MixedUsage-based - FirstRate Data
Vendor of historical intraday market data (1-minute to daily bars, tick and options) for US stocks, ETFs, futures, indices, crypto and FX, delivered as zipped CSV bundles under a perpetual licence
ProprietaryPaid - Interactive Brokers API
Programmatic trading and market-data access to Interactive Brokers accounts through the TWS API, the REST-based Web API and FIX
ProprietaryUsage-based - Nasdaq Data Link
Nasdaq's marketplace for financial, economic and alternative datasets (formerly Quandl) with a REST API, time-series and table endpoints and Python, R and Excel clients
ProprietaryFreemium - OpenFIGI
Free API and web tool from Bloomberg for mapping tickers, ISINs, CUSIPs and other identifiers to public-domain FIGI instrument identifiers, with search and filter endpoints
ProprietaryFree - SEC EDGAR
The SEC's free public filing system: company and full-text search, bulk index and feed archives, and data.sec.gov JSON APIs for submissions and XBRL financial facts, subject to a fair-access rate policy
ProprietaryFree - Wharton Research Data Services (WRDS)
Institution-subscribed research data platform from Wharton hosting CRSP, Compustat, TAQ, OptionMetrics and dozens of other vendors' databases with web queries, SQL, SAS, Python and R access
ProprietaryEnterprise - yfinance
Open-source Python library that downloads price history, fundamentals, options chains and fund data from Yahoo Finance's unofficial endpoints for research and education
Open sourceFree
Sources & verification
Primary sources consulted for this record. Claims are tied to the fields each source supports; the automated link checker re-verifies every URL on a schedule.
- Official documentationchecked Nov 1, 2026
- Official sitechecked Nov 1, 2026
- Policy pageTerms of Service | Massivechecked Nov 1, 2026
https://massive.com/legal/terms
Supports: limitations
Separate Individuals and Businesses terms
- Pricing pagechecked Nov 1, 2026
- Release notesPolygon is now Massivechecked Nov 1, 2026
https://massive.com/blog/polygon-is-now-massive
Supports: aliases, product_status, description
Rename effective 30 Oct 2025; legacy endpoints to be phased out with notice
- Confidence
- High
- Reviewed
- Nov 1, 2026
- Links
- Verified · Nov 2, 2026
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