Researched: 2026-02-20

Polygon.io Overview (Baseline)

Polygon.io (recently rebranding to “Massive”) is a purpose-built market data platform targeting developers, quants, and algorithmic traders who need high-quality, low-latency data at scale.

Data Types: US stocks, options (with analytics), forex, crypto, indices, futures Historical Depth: 25 years for US stocks; 30+ years for financials and dividends Real-time: Yes — WebSocket latency <20ms for stocks/options, <40ms for crypto, <200ms for forex Free Tier: 5 API calls/minute; aggregate bars only (no quotes/trades on free) Paid Plans:

  • Stocks Developer: ~$7/month
  • Stocks Starter: ~$29/month (5 years history, unlimited calls)
  • Stocks Advanced: ~$200/month (full real-time, unlimited calls)
  • Stocks + Crypto + Forex bundle: ~$249/month
  • Options add-on priced separately; full premium stack ~$449/month

Target Users: Developers, algo traders, quants, fintech startups Key Strengths: Best-in-class WebSocket streaming, normalized multi-asset data, tick-level accuracy, strong options coverage, no call limits on paid plans, WebSocket latency <20ms Key Weaknesses: Free tier is nearly unusable (5 req/min, aggregate bars only); cost scales steeply; weak fundamental/financials data vs dedicated providers; primarily US-focused for real-time


Competitor Analyses

1. Alpha Vantage

Website: https://www.alphavantage.co Overview: One of the most widely used budget-friendly APIs, especially popular for retail traders and individual developers. Official NASDAQ-licensed data vendor.

DimensionDetails
Data TypesUS/global equities, ETFs, mutual funds, FX, crypto, commodities, US options, 60+ technical indicators, economic indicators
Free Plan25 API calls/day (was recently reduced from higher limit)
Paid PlansStarting at $49.99/month (75 req/min); scales by req/min rate
Rate LimitsFree: 5 req/min, 25/day. Paid: 75–1,200 req/min depending on tier
Historical Depth20+ years for equities
Real-time vs Delayed15-minute delayed on free; real-time on paid plans (exchange-approved)
Target UsersRetail investors, individual developers, academics, small teams

Strengths vs Polygon:

  • Much lower entry price (200/month for advanced)
  • 60+ built-in technical indicators (no need to compute yourself)
  • Broad global coverage including international equities
  • Good fundamental data and economic indicators
  • Official NASDAQ vendor status adds credibility

Weaknesses vs Polygon:

  • Free tier 25 calls/day is nearly useless for real development
  • No WebSocket/streaming — REST only
  • Inferior for high-frequency or real-time trading applications
  • Rate limits remain the main constraint; support is sparse
  • Not suitable for tick-level or options analytics

2. Alpaca

Website: https://alpaca.markets Overview: Primarily a commission-free brokerage API for algorithmic trading, with a strong market data layer bundled in. Unique in that data and trading are tightly coupled.

DimensionDetails
Data TypesUS stocks, ETFs, crypto (no options data, no forex, no futures)
Free PlanDefault free tier — IEX exchange feed for stocks only (not consolidated tape), 200 req/min
Paid PlansAlgo Trader Plus — ~$99/month (consolidated tape, full market coverage)
Rate LimitsFree: 200 req/min. Paid: higher limits
Historical DepthBars going back several years; limited tick history
Real-time vs DelayedReal-time on paid via consolidated CTA/UTP feeds; IEX-only (limited) on free
Target UsersAlgorithmic traders, developers building automated trading bots

Strengths vs Polygon:

  • All-in-one data + brokerage execution in a single API
  • More efficient multi-symbol queries (1 request = 20 symbols vs 20 requests on Polygon)
  • Much better free tier rate limits (200 req/min vs 5 on Polygon)
  • 200–449/month on Polygon for equivalent coverage
  • Paper trading environment included

Weaknesses vs Polygon:

  • No options, no forex, no futures — US stocks/ETFs and crypto only
  • Not a pure data provider — tightly coupled to their brokerage infrastructure
  • Less historical depth than Polygon
  • Less suitable if you don’t also want brokerage functionality
  • Lower latency guarantees than Polygon for pure data use

Website: https://data.nasdaq.com Overview: Acquired by Nasdaq in 2018 from Quandl. Focused on alternative, economic, and curated institutional datasets. Not a typical real-time price feed provider.

DimensionDetails
Data Types250+ datasets: macro/economic data, alternative data, commodities, some equities EOD; dataset quality varies widely
Free Plan40 free datasets; 300 calls/10 seconds, 50,000 calls/day
Paid PlansPer-dataset subscription pricing; varies widely; premium data can be very expensive
Rate LimitsFree: 300 calls/10s, 50K/day. Premium: 5,000 calls/10min, 720K/day
Historical DepthVaries by dataset — some go back decades
Real-time vs DelayedPrimarily EOD and historical; no real-time price feeds
Target UsersInstitutional investors, hedge funds, quant researchers, economists

Strengths vs Polygon:

  • Unique alternative and economic datasets not available elsewhere
  • Strong institutional credibility (Nasdaq brand)
  • High API rate limits on free tier (by calls/day)
  • Curated, vetted data quality for research datasets

Weaknesses vs Polygon:

  • No real-time market data — primarily historical/EOD
  • Pricing for premium datasets can be very high
  • Not suitable for trading applications or live feeds
  • Dataset quality and availability is inconsistent across the catalog
  • No WebSocket streaming

4. Yahoo Finance API (Unofficial)

Website: https://finance.yahoo.com (no official API) Overview: Yahoo Finance’s official API was discontinued in 2017. What exists today is the yfinance Python library (and similar tools) that scrape Yahoo Finance’s web interface. Also available through RapidAPI third-party wrappers.

DimensionDetails
Data TypesUS/global equities, ETFs, mutual funds, options chains, crypto, forex (basic), indices, fundamentals
Free PlanEffectively free via yfinance library (no API key needed); rate limits are informal
Paid PlansVia RapidAPI marketplace; third-party hosted, not official
Rate LimitsNo official limits; aggressive scraping can result in IP blocks
Historical DepthSubstantial — decades of EOD data for major tickers
Real-time vs Delayed15-minute delayed for most data; no official real-time
Target UsersRetail investors, Python developers, students, hobbyists

Strengths vs Polygon:

  • Completely free with no API key via yfinance
  • Broad global coverage for EOD data
  • Easy to use — massive Python ecosystem
  • Options chain data available on free basis

Weaknesses vs Polygon:

  • Unofficial — no SLA, no support, can break without warning
  • Not suitable for production systems
  • No WebSocket / real-time streaming
  • Yahoo can block access; pipeline failures can be silent
  • No historical tick data
  • Not a viable comparison for professional use cases

5. IEX Cloud

Status: SHUT DOWN August 31, 2024

IEX Cloud was a popular developer-friendly platform with a pay-as-you-go credit model. It was officially discontinued when IEX (the exchange operator) decided to refocus on core exchange operations. It is no longer available. Former users migrated to Alpha Vantage, Polygon.io, Twelve Data, and others.


6. Marketstack

Website: https://marketstack.com Overview: A product from the apilayer/iLayer family. Focuses on global EOD stock data across 70+ exchanges. Simple REST API with straightforward pricing tiers.

DimensionDetails
Data TypesUS and international equities EOD, intraday (Professional+), historical; no crypto, no options, no forex
Free Plan100 requests/month
Paid PlansBasic: 49.99/month (100K req, real-time + full history), Business: custom
Rate LimitsReal-time endpoints: 1 API call/minute (Professional+)
Historical DepthFull historical on Professional+; 10 years on Basic
Real-time vs DelayedEOD/delayed on Basic; real-time on Professional+
Target UsersDevelopers needing global EOD data, small applications, budget-conscious builders

Strengths vs Polygon:

  • Very affordable entry point (29+ on Polygon)
  • 30,000+ tickers across 70+ global exchanges
  • Simple clean API design, easy to integrate

Weaknesses vs Polygon:

  • No streaming/WebSocket
  • No options, no crypto, no forex
  • 1 call/minute rate limit on real-time endpoints is very restrictive
  • Not suitable for algorithmic trading
  • Free tier of 100 requests/month is functionally useless
  • Data quality and depth inferior to Polygon for US markets

7. Tiingo

Website: https://www.tiingo.com Overview: A data platform with strong EOD coverage and a respected reputation for clean, multi-sourced data. Popular with Python quant researchers. Provides IEX real-time feed as a separate product.

DimensionDetails
Data TypesUS/Chinese equities, ETFs, mutual funds (65,000+ tickers), crypto via IEX, fundamentals, news
Free PlanUp to 50 symbols/hour; 30+ years historical EOD data included free
Paid PlansTiingo Power: unlocks news API, expanded fundamental data (15+ years), higher limits; pricing not fully disclosed publicly
Rate LimitsFree: 50 symbols/hour. Paid varies
Historical Depth50+ years for some tickers on EOD data; 5 years fundamentals (free), 15+ years (paid)
Real-time vs DelayedIEX real-time product available separately; EOD is end-of-day
Target UsersPython quant developers, retail traders, researchers, small hedge funds

Strengths vs Polygon:

  • Exceptional historical depth — 50+ years for some tickers (free)
  • Data quality is multi-sourced with error-checking (3+ data sources per feed)
  • More affordable than Polygon for historical research
  • 65,000+ tickers including mutual funds — broader coverage by count
  • Solid Python ecosystem

Weaknesses vs Polygon:

  • No WebSocket streaming (not a real-time trading data provider)
  • No options data
  • Limited forex and crypto coverage
  • Pricing for paid tiers is not transparent
  • Not suitable for HFT or tick-level trading data
  • Real-time requires separate IEX product

8. Financial Modeling Prep (FMP)

Website: https://site.financialmodelingprep.com Overview: Specializes in fundamental financial data — income statements, balance sheets, DCF models, analyst ratings, ESG, earnings calendars. Strong for fundamental analysts and valuation-focused developers.

DimensionDetails
Data Types70,000+ global securities; financial statements (income/balance/cash flow), real-time quotes, historical prices, crypto, commodities, indices, ETF holdings, ESG, earnings, analyst ratings
Free Plan500MB trailing 30-day bandwidth; limited endpoints
Paid PlansStarter: 20GB/month, Premium: 50GB, Ultimate: 150GB, Build: 100GB, Enterprise: 1TB+ (prices not publicly listed — contact required for most)
Rate LimitsBandwidth-based model (MB/GB consumed), not per-request
Historical Depth30+ years across 46 countries, 70,000+ securities
Real-time vs DelayedReal-time quotes available on paid tiers
Target UsersFundamental analysts, valuation modelers, portfolio managers, fintech app developers, screener builders

Strengths vs Polygon:

  • Deepest fundamental data (SEC EDGAR-sourced financials, DCF models, ratios)
  • Broadest global coverage: 70,000+ securities across 46 countries
  • Historical fundamentals going back 30+ years
  • ETF and mutual fund holdings data
  • ESG scores, analyst ratings, earnings estimates
  • Better suited for equity research than Polygon

Weaknesses vs Polygon:

  • Bandwidth-based pricing model is harder to predict/budget
  • Opaque pricing — most plans require contacting sales
  • Not designed for real-time trading or WebSocket streaming
  • Data latency not competitive with Polygon for live feeds
  • Less suited for options, tick-level, or HFT applications

9. EOD Historical Data (EODHD)

Website: https://eodhd.com Overview: A well-regarded provider of global historical data and fundamental data. 150,000+ tickers globally. Popular with quants doing backtesting. Also offers real-time feeds.

DimensionDetails
Data TypesStocks, ETFs, funds, currencies worldwide; 150,000+ tickers; EOD, intraday, fundamentals, technical indicators, real-time feeds
Free Plan20 API calls/day; EOD data for past 1 year only
Paid PlansEOD Historical All World: 199/year); EOD+Intraday Extended: 99.99/month; All-In-One Business: $299/month
Rate LimitsVaries by plan
Historical DepthExtensive — 30+ years for most major markets
Real-time vs DelayedReal-time feeds available on higher tiers
Target UsersQuant researchers, systematic traders, institutional/academic users, backtesting platforms

Strengths vs Polygon:

  • Exceptional global breadth — 150,000+ tickers worldwide
  • Very affordable entry for historical data ($19.99/month)
  • Strong for international market coverage
  • Good alternative for post-IEX Cloud users
  • 50% student/academic discount
  • Real-time feeds available at scale

Weaknesses vs Polygon:

  • Free tier (20 calls/day) is barely functional
  • No options data analytics (limited options coverage)
  • WebSocket streaming less mature than Polygon
  • Lower brand recognition / smaller ecosystem vs Polygon
  • Business use requires All-In-One Business tier at $299/month

10. Benzinga

Website: https://www.benzinga.com/apis Overview: Primarily a financial news and sentiment data provider, not a price/OHLCV data API. Their core value is real-time news feeds, earnings, and alternative data for systematic trading signals.

DimensionDetails
Data TypesFinancial news (real-time), earnings data, options activity, analyst ratings, calendar data, market movers; limited price data
Free PlanFree trial available; AWS Marketplace free tier for basic news
Paid PlansCustom/quote-based — contact licensing@benzinga.com; entry-level plans for developers, enterprise pricing for institutions
Rate LimitsPlan-dependent; streaming news feeds available
Historical DepthHistorical news archives available; price history is limited
Real-time vs DelayedReal-time news streaming is core offering
Target UsersQuant funds using news signals, options traders monitoring unusual activity, fintech apps needing news/sentiment

Strengths vs Polygon:

  • Best-in-class real-time financial news API
  • Unique options flow / unusual activity data
  • Good for alternative data strategies (sentiment, earnings surprise)
  • AWS Marketplace availability for easy procurement

Weaknesses vs Polygon:

  • Not a price data provider — very limited OHLCV coverage
  • Opaque pricing; must contact sales for most tiers
  • Not suitable as a primary market data API
  • Largely complementary to rather than competitive with Polygon

11. Tradier

Website: https://tradier.com Overview: A broker-dealer and API platform. Like Alpaca, combines trading execution with market data. Unique in that API access is free for account holders. Focused on options traders.

DimensionDetails
Data TypesUS equities, options (strong options focus), streaming quotes
Free PlanAPI access free for all Tradier Brokerage account holders
Paid PlansBrokerage Pro plan: $10/month (commission-free trades + enhanced features)
Rate LimitsAPI access is per-account; limits tied to account tier
Historical DepthHistorical price data available; depth less than dedicated providers
Real-time vs DelayedReal-time quotes for account holders
Target UsersOptions traders, retail algorithmic traders, fintech apps needing brokerage + data

Strengths vs Polygon:

  • Free API access for any brokerage account holder
  • Strong options trading and data focus
  • Full execution + data in one API (like Alpaca)
  • No per-call charges as a brokerage customer

Weaknesses vs Polygon:

  • Must open a brokerage account to access the API
  • US equities and options only — no crypto, no forex, no global markets
  • Historical depth is limited compared to Polygon
  • Not suitable as a standalone data provider without brokerage relationship
  • Less scalable for high-volume data applications

12. Twelve Data

Website: https://twelvedata.com Overview: A fast-growing, developer-friendly API covering stocks, forex, ETFs, indices, and crypto with a clean interface and transparent pricing. Frequently cited as a top alternative to IEX Cloud post-shutdown.

DimensionDetails
Data TypesStocks (global), forex, ETFs, indices, crypto, commodities, 90+ technical indicators
Free Plan8 API calls/minute, 800 calls/day
Paid PlansGrow: starts at 99/month (610–1,597 req/min); top tier: $329/month
Rate LimitsFree: 8/min, 800/day. Paid: 55–1,597 req/min
Historical DepthYears of historical data; depth varies by asset class
Real-time vs DelayedReal-time data available; WebSocket streaming on paid plans
Target UsersDevelopers, retail traders, fintech startups, API-first applications

Strengths vs Polygon:

  • Transparent pricing with no hidden fees; cancel anytime
  • 800 calls/day on free tier — far more usable than Polygon’s 5/min
  • Global stock coverage (not just US)
  • 90+ technical indicators built-in
  • WebSocket streaming available
  • 99.95% uptime SLA advertised
  • 20% discount for students/startups

Weaknesses vs Polygon:

  • No options data
  • Less tick-level accuracy and lower latency guarantees vs Polygon
  • Smaller ecosystem and community than Polygon
  • Top tier at $329/month is comparable to Polygon pricing for serious use

14. Financial Datasets AI

Website: https://www.financialdatasets.ai Overview: A developer-focused financial data API emphasizing clean, well-structured data for building AI financial agents, portfolio management tools, and quantitative trading algorithms. Covers 30,000+ tickers with 30+ years of history. Offers both subscription and pay-as-you-go pricing.

DimensionDetails
Data TypesStock prices (real-time & historical), financial statements (income/balance/cash flow), insider transactions, institutional ownership, SEC filings (10-K, 10-Q, 8-K), analyst estimates, earnings data, news, business segment breakdowns
Free PlanPay-as-you-go with some free endpoints (company facts, earnings releases at $0.00)
Paid PlansDeveloper: 2,000/month (unlimited requests, data redistribution license, includes crypto); Enterprise: custom pricing (dedicated compute, priority support)
Pay-As-You-GoStock prices 0.04–0.02/req; analyst estimates $0.04/req
Rate LimitsDeveloper: 1,000 req/min; Pro: unlimited
Historical Depth30+ years, 30,000+ tickers, 100% market coverage
Real-time vs DelayedReal-time stock prices available
Target UsersAI/ML developers building financial agents, quant traders, fintech startups, portfolio tool builders

Strengths vs Polygon:

  • Strong fundamental data focus (financial statements, SEC filings, insider trades, institutional ownership)
  • Pay-as-you-go option — only pay for what you use, no minimum commitment
  • Developer: $200/mo gets 1,000 req/min (comparable to Polygon Advanced)
  • Clean, well-structured data specifically designed for AI/ML consumption
  • Analyst estimates and earnings data included
  • Business segment and geographic breakdowns (unique)

Weaknesses vs Polygon:

  • No WebSocket streaming — REST only
  • No options data
  • No forex data
  • No tick-level or intraday granularity mentioned
  • Pro tier at $2,000/mo is expensive (needed for redistribution rights)
  • Smaller/newer player — less ecosystem and community
  • No technical indicators built-in
  • US equities focused — limited global coverage

Summary Comparison Table

ProviderPrice EntryFree Tier QualityReal-TimeWebSocketOptionsGlobalHistorical DepthBest For
Polygon.io$29/mo (Starter)Poor (5 req/min)YesYes (<20ms)YesUS-focused25 yearsHFT, algo trading, real-time apps
Alpha Vantage$49.99/moPoor (25/day)Yes (paid)NoYesGood20+ yearsBudget developers, technicals
Alpaca$99/mo (all-in)Good (200 req/min)Yes (paid)YesNoUS onlyLimitedAlgo trading with execution
Nasdaq Data LinkPer datasetGood (50K/day)NoNoNoYesVariesAlternative/macro data research
Yahoo FinanceFreeExcellentNoNoBasicGoodDecadesHobbyists, Python scripts
IEX CloudSHUT DOWNN/AN/AN/AN/AN/AN/ADefunct (Aug 2024)
Marketstack$9.99/moVery Poor (100/mo)Yes (Pro+)NoNoExcellent10–full yearsGlobal EOD on a budget
TiingoFreemiumGood (50 sym/hr)Via IEXNoNoUS+China50+ yearsQuant research, deep history
FMPBandwidth-basedModerateYes (paid)NoLimitedExcellent30+ yearsFundamental analysis, valuation
EODHD$19.99/moVery Poor (20/day)Yes (paid)LimitedLimitedExcellent30+ yearsGlobal backtesting, research
BenzingaCustom/contactTrial onlyYes (news)Yes (news)Activity dataUSLimitedNews/sentiment/alternative data
TradierFree w/accountN/A (account req)YesNoYesUS onlyLimitedOptions traders using brokerage
Twelve Data$29/moGood (800/day)YesYes (paid)NoExcellentYearsDeveloper-friendly, global stocks
Financial Datasets AI$200/mo or PAYGFree endpointsYesNoNoUS-focused30+ yearsAI agents, fundamentals, SEC filings
Finnhub$49.99/moExcellent (60/min)YesYesLimitedGoodLimitedSentiment, alternative data, free

Key Takeaways

Use Polygon.io when:

  • You need low-latency WebSocket streaming (<20ms)
  • Options analytics are required at scale
  • You are building algorithmic trading infrastructure
  • Tick-level US market data accuracy is critical
  • Budget is not the primary constraint

Use Alpha Vantage when:

  • You need built-in technical indicators
  • Budget is a primary concern
  • You need global equity coverage affordably

Use Alpaca when:

  • You want data + trade execution in one API
  • You are building an automated trading bot
  • The 200–449 for your use case

Use Twelve Data when:

  • You want Polygon-like capabilities at a lower entry price
  • Global stock + forex + crypto coverage matters
  • A more generous free tier is important for prototyping

Use FMP when:

  • Fundamental analysis is the primary use case
  • You need global breadth (70,000+ securities, 46 countries)
  • DCF models, earnings, ESG, and analyst data are needed

Use EODHD when:

  • You need broad global historical data cheaply
  • Backtesting across international markets
  • Budget is constrained but professional-grade data is required

Use Tiingo when:

  • Deep historical US/China equity data is the focus
  • Research-grade data quality is important
  • You work primarily in Python

Use Financial Datasets AI when:

  • Building AI financial agents or LLM-powered finance tools
  • Fundamental data (financials, SEC filings, insider trades) is the primary need
  • You want pay-as-you-go flexibility without a monthly commitment
  • Clean, structured data for ML pipelines matters more than real-time speed

Use Nasdaq Data Link when:

  • Alternative/macro/economic datasets are required
  • Institutional-grade curated data matters
  • Price feeds are not the primary need

Sources