Polygon.io website screenshot

Polygon.io

Polygon.io (rebranded as Massive in early 2026) provides real-time and historical market data APIs across stocks, options, indices, forex, crypto, and futures via REST, WebSocket streaming, and S3-style flat files. APIs cover trades, quotes, aggregates, snapshots, ticker reference data, and corporate actions.

Polygon.io publishes 8 APIs on the APIs.io network, including Stocks API, Options API, Indices API, and 5 more. Tagged areas include Fintech, Market Data, Stocks, Options, and Forex.

The Polygon.io catalog on APIs.io includes 1 event-driven AsyncAPI specification and 1 Spectral governance ruleset.

Polygon.io’s developer surface includes authentication, developer portal, documentation, pricing, GitHub presence, and 7 more developer resources.

🌐 Visit website 📡 Source on GitHub
48.6/100 developing ▬ flat Agent 36/100 agent ready Full breakdown ↓
scored 2026-07-28 · rubric v0.6
AccessFreemiumSelf serve⚡ Free to try
8 APIs
FintechMarket DataStocksOptionsForexCryptoIndicesFuturesWebSocketsReal-timeHistorical

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-07-28 · rubric v0.6
Composite quality — 48.6/100 · developing
Contract Quality 17.0 / 25
Developer Ergonomics 5.7 / 20
Commercial Clarity 10.0 / 20
Operational Transparency 6.8 / 13
Governance 5.0 / 12
Discoverability 7.4 / 10
Agent readiness — 36/100 · agent ready
Machine-Readable Contract 18 / 18
Agentic Access Contract 10 / 10
MCP Server 0 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 6 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/polygon-io: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 8

Individual APIs this provider publishes, each with its own machine-readable definition.

Polygon.io Stocks API

Real-time and historical US equity market data including aggregates (minute/hour/day bars), trades, NBBO quotes, snapshots, ticker reference, splits, dividends, and financials. ...

Polygon.io Options API

OPRA-licensed options market data via REST and WebSocket: aggregates, trades, quotes, snapshots, contract reference, and option chains.

Polygon.io Indices API

Real-time and historical index values for major US and global indices via REST and WebSocket.

Polygon.io Forex API

Real-time and historical FX prices for 1,000+ currency pairs via REST and WebSocket.

Polygon.io Crypto API

Aggregates, trades, snapshots, level-2 books, and L2 streaming for crypto pairs across major exchanges.

Polygon.io Futures API

Real-time and historical futures market data including aggregates, trades, quotes, and snapshots.

Polygon.io Aggregates API

Aggregate (OHLC) bar data.

Polygon.io Reference API

Ticker reference data.

Scroll for all 8

Open Collections 1

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Polygon.io REST API (Stocks)

OPEN COLLECTION

Pricing Plans 1

Published pricing tiers and plan structures.

Polygon Io Plans Pricing

5 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Polygon Io Rate Limits

4 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

Polygon Io Finops

FINOPS

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Polygon.io WebSocket APIs

Streaming WebSocket APIs from Polygon.io (now operating as Massive) for real-time and delayed US Stocks, Options, Forex, Crypto, Indices, and Futures market data. Clients connec...

ASYNCAPI

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Polygon.io API Rules

9 rules · 1 errors 8 warnings

SPECTRAL

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Polygon Io Authentication

apiKey/http · 2 schemes

SECURITY

Polygon Io Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Polygon Io Agentic Access

3 operations

3 operations · 0 acting

AGENTIC

Resources

Get Started 1

Portal, sign-up, and the first successful call

Portal
Portal

Documentation 1

Reference material describing how the API behaves

Documentation
Documentation

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess
AgenticAccess

Build 1

SDKs, sample code, and the tooling you integrate with

GitHub
GitHub

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity
DomainSecurity
 Authentication
Authentication

Operate 2

Status, limits, changes, and where to get help

StatusPage
StatusPage
 RateLimits
RateLimits

Commercial 3

Pricing, plans, and the legal terms of use

Pricing
Pricing
 Plans
Plans
 FinOps
FinOps

Company 1

The organization behind the API

LinkedIn
LinkedIn

Source (apis.yml)

apis.yml Raw ↑ 
aid: polygon-io
url: https://raw.githubusercontent.com/api-evangelist/polygon-io/refs/heads/main/apis.yml
name: Polygon.io
kind: company
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  label: Freemium · Self-serve signup
  confidence: high
  source:
  - plans
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/polygon-io.png
tags:
- Fintech
- Market Data
- Stocks
- Options
- Forex
- Crypto
- Indices
- Futures
- WebSockets
- Real-time
- Historical
created: '2026-05-08'
modified: '2026-05-29'
specificationVersion: '0.19'
description: Polygon.io (rebranded as Massive in early 2026) provides real-time and historical market data APIs across stocks,
  options, indices, forex, crypto, and futures via REST, WebSocket streaming, and S3-style flat files. APIs cover trades,
  quotes, aggregates, snapshots, ticker reference data, and corporate actions.
apis:
- aid: polygon-io:stocks-api
  name: Polygon.io Stocks API
  tags:
  - Stocks
  - Equities
  - Market Data
  - Real-time
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  baseURL: https://api.polygon.io
  humanURL: https://polygon.io/docs/stocks
  description: Real-time and historical US equity market data including aggregates (minute/hour/day bars), trades, NBBO quotes,
    snapshots, ticker reference, splits, dividends, and financials. Available via REST and WebSocket.
  properties:
  - type: Documentation
    url: https://polygon.io/docs/stocks
  - type: AsyncAPI
    url: asyncapi/polygon-io-asyncapi.yml
  x-features:
  - Real-time and historical aggregates
  - NBBO trades and quotes
  - Snapshots and ticker reference
  - Corporate actions
  - WebSocket streaming
  x-use-cases:
  - Power equity charts and tickers
  - Backtest strategies on historical bars
  - Stream live trades into surveillance systems
- aid: polygon-io:options-api
  name: Polygon.io Options API
  tags:
  - Options
  - OPRA
  - Market Data
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  baseURL: https://api.polygon.io
  humanURL: https://polygon.io/docs/options
  description: 'OPRA-licensed options market data via REST and WebSocket: aggregates, trades, quotes, snapshots, contract
    reference, and option chains.'
  properties:
  - type: Documentation
    url: https://polygon.io/docs/options
  - type: AsyncAPI
    url: asyncapi/polygon-io-asyncapi.yml
  x-features:
  - OPRA-licensed options data
  - Snapshot and chain endpoints
  - Greeks and IV (paid tiers)
  - WebSocket streaming
  x-use-cases:
  - Options trading research
  - Volatility surface modeling
  - Greeks dashboards
- aid: polygon-io:indices-api
  name: Polygon.io Indices API
  tags:
  - Indices
  - Market Data
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  baseURL: https://api.polygon.io
  humanURL: https://polygon.io/docs/indices
  description: Real-time and historical index values for major US and global indices via REST and WebSocket.
  properties:
  - type: Documentation
    url: https://polygon.io/docs/indices
  - type: AsyncAPI
    url: asyncapi/polygon-io-asyncapi.yml
  x-features:
  - Index values and aggregates
  - Snapshots
  - WebSocket streaming
  x-use-cases:
  - Benchmark performance tracking
  - Index-based product pricing
- aid: polygon-io:forex-api
  name: Polygon.io Forex API
  tags:
  - Forex
  - FX
  - Currencies
  - Market Data
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  baseURL: https://api.polygon.io
  humanURL: https://polygon.io/docs/forex
  description: Real-time and historical FX prices for 1,000+ currency pairs via REST and WebSocket.
  properties:
  - type: Documentation
    url: https://polygon.io/docs/forex
  - type: AsyncAPI
    url: asyncapi/polygon-io-asyncapi.yml
  x-features:
  - 1,000+ currency pairs
  - Aggregates and quotes
  - WebSocket streaming
  x-use-cases:
  - Multi-currency reporting
  - FX trading strategies
- aid: polygon-io:crypto-api
  name: Polygon.io Crypto API
  tags:
  - Crypto
  - Cryptocurrency
  - Market Data
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  baseURL: https://api.polygon.io
  humanURL: https://polygon.io/docs/crypto
  description: Aggregates, trades, snapshots, level-2 books, and L2 streaming for crypto pairs across major exchanges.
  properties:
  - type: Documentation
    url: https://polygon.io/docs/crypto
  - type: AsyncAPI
    url: asyncapi/polygon-io-asyncapi.yml
  x-features:
  - Aggregated cross-exchange data
  - Level-2 order books
  - WebSocket streaming
  x-use-cases:
  - Crypto trading and analytics
  - Cross-exchange arbitrage research
- aid: polygon-io:futures-api
  name: Polygon.io Futures API
  tags:
  - Futures
  - Market Data
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  baseURL: https://api.polygon.io
  humanURL: https://polygon.io/docs/futures
  description: Real-time and historical futures market data including aggregates, trades, quotes, and snapshots.
  properties:
  - type: Documentation
    url: https://polygon.io/docs/futures
  - type: AsyncAPI
    url: asyncapi/polygon-io-asyncapi.yml
  x-features:
  - CME-licensed futures data
  - Aggregates and snapshots
  - Continuous contracts
  x-use-cases:
  - Futures trading research
  - Commodities and rates analytics
- aid: polygon-io:polygon-io-aggregates-api
  name: Polygon.io Aggregates API
  description: Aggregate (OHLC) bar data.
  humanURL: https://polygon.io/docs/stocks
  baseURL: https://api.polygon.io
  tags:
  - Aggregates
  properties:
  - type: OpenAPI
    url: openapi/polygon-io-aggregates-api-openapi.yml
- aid: polygon-io:polygon-io-reference-api
  name: Polygon.io Reference API
  description: Ticker reference data.
  humanURL: https://polygon.io/docs/stocks
  baseURL: https://api.polygon.io
  tags:
  - Reference
  properties:
  - type: OpenAPI
    url: openapi/polygon-io-reference-api-openapi.yml
common:
- type: AgenticAccess
  url: agentic-access/polygon-io-agentic-access.yml
- type: DomainSecurity
  url: security/polygon-io-domain-security.yml
- type: Authentication
  url: authentication/polygon-io-authentication.yml
- type: LinkedIn
  url: https://www.linkedin.com/company/polygon-io
- type: Portal
  url: https://polygon.io/
- type: Documentation
  url: https://polygon.io/docs
- type: Pricing
  url: https://polygon.io/pricing
- type: StatusPage
  url: https://status.polygon.io/
- type: GitHub
  url: https://github.com/polygon-io
- type: Plans
  url: plans/polygon-io-plans-pricing.yml
- type: RateLimits
  url: rate-limits/polygon-io-rate-limits.yml
- type: FinOps
  url: finops/polygon-io-finops.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com