The short answer

The cheapest stock market data API in 2026 depends on the job. Alpaca's free IEX feed ($0) is the real-time floor (small slice of volume), Finnhub gives free real-time US quotes at 60 calls/minute, and the cheapest full SIP tape is Alpaca Algo Trader Plus ($99/mo) or Polygon Advanced ($199/mo). Every cheap tier hides one deal-breaker.

The cheapest stock market data API in 2026 depends on the job. For genuinely-free real-time, Alpaca's IEX feed ($0) is the floor, with the catch that IEX is a small slice of consolidated volume. For free real-time US quotes with a usable rate limit, Finnhub (60 calls/min, $0). For the cheapest path to a full real-time SIP tape, you pay: Alpaca Algo Trader Plus at $99/mo or Polygon Advanced at $199/mo. Every "cheap" tier hides one deal-breaker; the Data Vendor TCO surfaces the all-in number.

TL;DR

Job Cheapest option Price The catch
Free real-time (any) Alpaca IEX feed $0 IEX is a fraction of consolidated volume
Free real-time quotes + WebSocket Finnhub free $0 personal/non-commercial use only
Free EOD / historical Polygon Basic, Alpaca $0 5 calls/min; 15-min historical cap (Alpaca)
Cheapest full SIP real-time Alpaca Algo Trader Plus $99/mo requires Alpaca brokerage account
Flat-rate intraday (delayed) Polygon Starter $29/mo 15-minute delayed until $199 Advanced

Alpaca and Polygon figures verified 2026-05-25 against official pages. Finnhub free-tier limit is documented; its paid prices are not statically verifiable (noted below).

The genuinely-free floor: Alpaca IEX

Alpaca's free Basic market-data tier is the IEX feed: real-time data, 200 API calls per minute, and up to 30 symbols over WebSocket, at $0 (verified 2026-05-25, docs.alpaca.markets). It is real-time and it is free, which sounds unbeatable until the catch: IEX is a single exchange representing a small share of US consolidated equity volume, so quotes can diverge from NBBO and last-trade prints miss the off-IEX tape. For research and signal prototyping it is fine; for execution-grade pricing it is not. The full IEX-vs-SIP breakdown is in Alpaca Free Tier: IEX vs SIP 2026.

The other free-tier constraint to know: on Alpaca's free plan, historical data is limited to the latest 15 minutes; older history needs a paid tier.

The best free rate limit: Finnhub

If the bottleneck is calls-per-minute rather than feed quality, Finnhub's free tier gives 60 calls/minute (versus Alpaca's 200 trading-API limit and Polygon's 5), free real-time US quotes, and a free WebSocket. The deal-breaker: the free tier is personal/non-commercial use only. For a commercial product you must pay, and the paid prices are not statically verifiable on the JS-rendered pricing page. Detail in Is Finnhub Free? 2026.

The cheapest real-time SIP tape

When the strategy needs the full consolidated tape (NBBO-quality quotes, complete trade prints), the genuinely-free options run out and you pay for SIP:

  • Alpaca Algo Trader Plus — $99/mo: full SIP across all US exchanges plus the OPRA options feed, 10,000 API calls/minute, unlimited WebSocket subscriptions (verified 2026-05-25). The catch is you need an Alpaca brokerage account.
  • Polygon.io (Massive) Advanced — $199/mo: full real-time stocks, unlimited API calls, flat-rate (verified 2026-05-25, massive.com/pricing). The catch is the price step from the $79 Developer tier, which is still 15-minute delayed.

At $99 vs $199 for full real-time, Alpaca is the cheaper SIP path if you are willing to open the brokerage account; Polygon is the data-only flat-rate alternative.

The cheapest fundamentals-inclusive tier

For fundamentals (not just prices), the budget pick is Tiingo, whose low entry tier is modeled at $10/mo in the Data Vendor TCO engine catalogue (EOD + news), with fundamentals on the higher Power tier (~$50/mo snapshot). Confirm current pricing on Tiingo's page; treat these as the engine snapshot from 2026-04-20.

Every cheap tier's deal-breaker

The one-line trap per option, so you do not get surprised in production:

Option Deal-breaker
Alpaca IEX free IEX volume share is small; not NBBO-grade
Finnhub free personal/non-commercial use only
Polygon Basic free 5 calls/min, end-of-day only
Alpaca free historical latest-15-minutes cap on history
Polygon Starter $29 15-minute delayed, not real-time
Tiingo free excludes fundamentals + news APIs

The economics, computed live

The Data Vendor TCO engine ranks the field on annual all-in cost for a small-universe daily-resolution profile, the canonical cheapest-path use case. The verified output block at the foot of the page is computed from the shipped engine bundle, not typed by hand. The vendor snapshot dates to 2026-04-20; the Alpaca and Polygon figures in the prose above are re-verified to 2026-05-25.

Decision guidance

  • Free, real-time, research-only: Alpaca IEX (accept the volume-share caveat).
  • Free, best rate limit, prototyping: Finnhub (personal use only).
  • Cheapest full real-time SIP: Alpaca Algo Trader Plus $99/mo (brokerage account required).
  • Flat-rate data-only: Polygon Starter $29 delayed, Advanced $199 real-time.
  • Fundamentals on a budget: Tiingo entry tier.

Connects to

References

  • Alpaca. "About Market Data API." docs.alpaca.markets/us/docs/about-market-data-api, verified 2026-05-25 (free IEX, Algo Trader Plus $99/mo, 10,000 calls/min).
  • Massive (formerly Polygon.io). "Pricing." massive.com/pricing, verified 2026-05-25 (Basic $0 EOD, Starter $29, Advanced $199 real-time).
  • Finnhub. "Pricing / API docs." finnhub.io, accessed 2026-05-25 (free 60 calls/min, personal-use restriction; paid prices not statically verifiable).
  • Tiingo. "Pricing." tiingo.com/about/pricing, accessed 2026-05-25 (figures from Data Vendor TCO engine snapshot 2026-04-20).

Verified engine output

Show the recompute-verified inputs and outputs
Small-universe daily-resolution cheapest-path profile — annual TCO ranked across vendors
Inputs
universesmall
resolutiondaily
needs_livefalse
needs_optionsfalse
needs_futuresfalse
Result
scenario › universesmall
scenario › resolutiondaily
scenario › history5-year
scenario › needs livefalse
scenario › needs optionsfalse
scenario › needs futuresfalse
ranked › row 1 › vendor › idalpaca
ranked › row 1 › vendor › nameAlpaca Markets
ranked › row 1 › vendor › urlhttps://alpaca.markets
ranked › row 1 › vendor › short pitchBroker-bundled market data. Generous free tier via IEX feed; SIP feed requires paid plan.
ranked › row 1 › vendor › has overagefalse
ranked › row 1 › vendor › last checked2026-05-25
ranked › row 1 › vendor › tiers › row 1 › nameFree (IEX feed)
ranked › row 1 › vendor › tiers › row 1 › monthly0
ranked › row 1 › vendor › tiers › row 1 › includes livetrue
ranked › row 1 › vendor › tiers › row 1 › includes optionsfalse
ranked › row 1 › vendor › tiers › row 1 › includes futuresfalse
ranked › row 1 › vendor › tiers › row 1 › resolutions › row 1daily
ranked › row 1 › vendor › tiers › row 1 › resolutions › row 2minute
ranked › row 1 › vendor › tiers › row 1 › notes › row 1IEX feed only (subset of volume)
ranked › row 1 › vendor › tiers › row 1 › notes › row 2Free with Alpaca brokerage account
ranked › row 1 › vendor › tiers › row 2 › nameAlgo Trader Plus (SIP feed)
ranked › row 1 › vendor › tiers › row 2 › monthly99
ranked › row 1 › vendor › tiers › row 2 › includes livetrue
ranked › row 1 › vendor › tiers › row 2 › includes optionstrue
ranked › row 1 › vendor › tiers › row 2 › includes futuresfalse
ranked › row 1 › vendor › tiers › row 2 › resolutions › row 1daily
ranked › row 1 › vendor › tiers › row 2 › resolutions › row 2minute
ranked › row 1 › vendor › tiers › row 2 › resolutions › row 3second
ranked › row 1 › vendor › tiers › row 2 › resolutions › row 4tick
ranked › row 1 › vendor › tiers › row 2 › notes › row 1Full SIP consolidated tape
ranked › row 1 › vendor › tiers › row 2 › notes › row 2Options chains included
ranked › row 1 › tier › nameFree (IEX feed)
ranked › row 1 › tier › monthly0
ranked › row 1 › tier › includes livetrue
ranked › row 1 › tier › includes optionsfalse
ranked › row 1 › tier › includes futuresfalse
ranked › row 1 › tier › resolutions › row 1daily
ranked › row 1 › tier › resolutions › row 2minute
ranked › row 1 › tier › notes › row 1IEX feed only (subset of volume)
ranked › row 1 › tier › notes › row 2Free with Alpaca brokerage account
ranked › row 1 › monthly0
ranked › row 1 › one time0
ranked › row 1 › annual total0
ranked › row 1 › meets resolutiontrue
ranked › row 1 › meets livetrue
ranked › row 1 › meets optionstrue
ranked › row 1 › meets futurestrue
ranked › row 1 › meets alltrue
ranked › row 2 › vendor › idtiingo
ranked › row 2 › vendor › nameTiingo
ranked › row 2 › vendor › urlhttps://www.tiingo.com
ranked › row 2 › vendor › short pitchStrong fundamentals + EOD pricing at low cost. Limited intraday. Favorite for long-horizon research.
ranked › row 2 › vendor › has overagefalse
ranked › row 2 › vendor › last checked2026-04-20
ranked › row 2 › vendor › tiers › row 1 › nameTiingo Starter
ranked › row 2 › vendor › tiers › row 1 › monthly10
ranked › row 2 › vendor › tiers › row 1 › includes livefalse
ranked › row 2 › vendor › tiers › row 1 › includes optionsfalse
ranked › row 2 › vendor › tiers › row 1 › includes futuresfalse
ranked › row 2 › vendor › tiers › row 1 › resolutions › row 1daily
ranked › row 2 › vendor › tiers › row 1 › notes › row 1EOD equities
ranked › row 2 › vendor › tiers › row 1 › notes › row 2News API included
ranked › row 2 › vendor › tiers › row 1 › notes › row 3Price unconfirmed 2026-05-25 — official pricing page not machine-readable
ranked › row 2 › vendor › tiers › row 2 › nameTiingo Power
ranked › row 2 › vendor › tiers › row 2 › monthly50
ranked › row 2 › vendor › tiers › row 2 › includes livefalse
ranked › row 2 › vendor › tiers › row 2 › includes optionsfalse
ranked › row 2 › vendor › tiers › row 2 › includes futuresfalse
ranked › row 2 › vendor › tiers › row 2 › resolutions › row 1daily
ranked › row 2 › vendor › tiers › row 2 › resolutions › row 2minute
ranked › row 2 › vendor › tiers › row 2 › notes › row 1Intraday bars
ranked › row 2 › vendor › tiers › row 2 › notes › row 2Crypto data
ranked › row 2 › vendor › tiers › row 2 › notes › row 3Fundamentals included
ranked › row 2 › tier › nameTiingo Starter
ranked › row 2 › tier › monthly10
ranked › row 2 › tier › includes livefalse
ranked › row 2 › tier › includes optionsfalse
ranked › row 2 › tier › includes futuresfalse
ranked › row 2 › tier › resolutions › row 1daily
ranked › row 2 › tier › notes › row 1EOD equities
ranked › row 2 › tier › notes › row 2News API included
ranked › row 2 › tier › notes › row 3Price unconfirmed 2026-05-25 — official pricing page not machine-readable
ranked › row 2 › monthly10
ranked › row 2 › one time0
ranked › row 2 › annual total120
ranked › row 2 › meets resolutiontrue
ranked › row 2 › meets livetrue
ranked › row 2 › meets optionstrue
ranked › row 2 › meets futurestrue
ranked › row 2 › meets alltrue
ranked › row 3 › vendor › iddatabento
ranked › row 3 › vendor › nameDatabento
ranked › row 3 › vendor › urlhttps://databento.com
ranked › row 3 › vendor › short pitchPer-unit metered pricing. Strong for institutional-quality tick + L2 data. No subscriptions on base offer.
ranked › row 3 › vendor › has overagetrue
ranked › row 3 › vendor › last checked2026-05-25
ranked › row 3 › vendor › tiers › row 1 › nameDatabento metered (typical retail)
ranked › row 3 › vendor › tiers › row 1 › monthly125
ranked › row 3 › vendor › tiers › row 1 › includes livetrue
ranked › row 3 › vendor › tiers › row 1 › includes optionsfalse
ranked › row 3 › vendor › tiers › row 1 › includes futurestrue
ranked › row 3 › vendor › tiers › row 1 › resolutions › row 1daily
ranked › row 3 › vendor › tiers › row 1 › resolutions › row 2minute
ranked › row 3 › vendor › tiers › row 1 › resolutions › row 3second
ranked › row 3 › vendor › tiers › row 1 › resolutions › row 4tick
ranked › row 3 › vendor › tiers › row 1 › resolutions › row 5level2
ranked › row 3 › vendor › tiers › row 1 › notes › row 1Usage-metered: historical is pay-as-you-go priced per GB (uncompressed binary), no subscription required; $125 free credits on signup
ranked › row 3 › vendor › tiers › row 1 › notes › row 2Subscription option: Standard $199/mo (historical core schemas + 1yr L1 / 1mo L2-L3); $125/mo modeled typical retail metered spend
ranked › row 3 › vendor › tiers › row 1 › notes › row 3Live data + dedicated support on Plus ($1,399/mo, annual); Unlimited $3,500/mo (verified 2026-05-25)
ranked › row 3 › vendor › tiers › row 1 › notes › row 4Per-GB cost scales aggressively with universe and resolution
ranked › row 3 › tier › nameDatabento metered (typical retail)
ranked › row 3 › tier › monthly125
ranked › row 3 › tier › includes livetrue
ranked › row 3 › tier › includes optionsfalse
ranked › row 3 › tier › includes futurestrue
ranked › row 3 › tier › resolutions › row 1daily
ranked › row 3 › tier › resolutions › row 2minute
ranked › row 3 › tier › resolutions › row 3second
ranked › row 3 › tier › resolutions › row 4tick
ranked › row 3 › tier › resolutions › row 5level2
ranked › row 3 › tier › notes › row 1Usage-metered: historical is pay-as-you-go priced per GB (uncompressed binary), no subscription required; $125 free credits on signup
ranked › row 3 › tier › notes › row 2Subscription option: Standard $199/mo (historical core schemas + 1yr L1 / 1mo L2-L3); $125/mo modeled typical retail metered spend
ranked › row 3 › tier › notes › row 3Live data + dedicated support on Plus ($1,399/mo, annual); Unlimited $3,500/mo (verified 2026-05-25)
ranked › row 3 › tier › notes › row 4Per-GB cost scales aggressively with universe and resolution
ranked › row 3 › monthly13
ranked › row 3 › one time0
ranked › row 3 › annual total150
ranked › row 3 › meets resolutiontrue
ranked › row 3 › meets livetrue
ranked › row 3 › meets optionstrue
ranked › row 3 › meets futurestrue
ranked › row 3 › meets alltrue
ranked › row 4 › vendor › idfmp
ranked › row 4 › vendor › nameFinancial Modeling Prep
ranked › row 4 › vendor › urlhttps://site.financialmodelingprep.com
ranked › row 4 › vendor › short pitchFundamentals-heavy. Earnings, filings, transcripts. Price data is a secondary offer.
ranked › row 4 › vendor › has overagefalse
ranked › row 4 › vendor › last checked2026-04-20
ranked › row 4 › vendor › tiers › row 1 › nameStarter
ranked › row 4 › vendor › tiers › row 1 › monthly14
ranked › row 4 › vendor › tiers › row 1 › includes livefalse
ranked › row 4 › vendor › tiers › row 1 › includes optionsfalse
ranked › row 4 › vendor › tiers › row 1 › includes futuresfalse
ranked › row 4 › vendor › tiers › row 1 › resolutions › row 1daily
ranked › row 4 › vendor › tiers › row 1 › notes › row 15 years history
ranked › row 4 › vendor › tiers › row 1 › notes › row 2250 API calls/day
ranked › row 4 › vendor › tiers › row 1 › notes › row 3Price unconfirmed 2026-05-25 — FMP list prices not consistently published
ranked › row 4 › vendor › tiers › row 2 › namePremium
ranked › row 4 › vendor › tiers › row 2 › monthly29
ranked › row 4 › vendor › tiers › row 2 › includes livefalse
ranked › row 4 › vendor › tiers › row 2 › includes optionsfalse
ranked › row 4 › vendor › tiers › row 2 › includes futuresfalse
ranked › row 4 › vendor › tiers › row 2 › resolutions › row 1daily
ranked › row 4 › vendor › tiers › row 2 › resolutions › row 2minute
ranked › row 4 › vendor › tiers › row 2 › notes › row 1Full history
ranked › row 4 › vendor › tiers › row 2 › notes › row 2750 calls/day
ranked › row 4 › vendor › tiers › row 3 › nameUltimate
ranked › row 4 › vendor › tiers › row 3 › monthly79
ranked › row 4 › vendor › tiers › row 3 › includes livetrue
ranked › row 4 › vendor › tiers › row 3 › includes optionsfalse
ranked › row 4 › vendor › tiers › row 3 › includes futuresfalse
ranked › row 4 › vendor › tiers › row 3 › resolutions › row 1daily
ranked › row 4 › vendor › tiers › row 3 › resolutions › row 2minute
ranked › row 4 › vendor › tiers › row 3 › resolutions › row 3second
ranked › row 4 › vendor › tiers › row 3 › notes › row 1Real-time
ranked › row 4 › vendor › tiers › row 3 › notes › row 2Unlimited calls
ranked › row 4 › tier › nameStarter
ranked › row 4 › tier › monthly14
ranked › row 4 › tier › includes livefalse
ranked › row 4 › tier › includes optionsfalse
ranked › row 4 › tier › includes futuresfalse
ranked › row 4 › tier › resolutions › row 1daily
ranked › row 4 › tier › notes › row 15 years history
ranked › row 4 › tier › notes › row 2250 API calls/day
ranked › row 4 › tier › notes › row 3Price unconfirmed 2026-05-25 — FMP list prices not consistently published
ranked › row 4 › monthly14
ranked › row 4 › one time0
ranked › row 4 › annual total168
ranked › row 4 › meets resolutiontrue
ranked › row 4 › meets livetrue
ranked › row 4 › meets optionstrue
ranked › row 4 › meets futurestrue
ranked › row 4 › meets alltrue
ranked › row 5 › vendor › idpolygon
ranked › row 5 › vendor › namePolygon.io
ranked › row 5 › vendor › urlhttps://polygon.io
ranked › row 5 › vendor › short pitchFlat-rate subscription. Real-time + historical for US equities. Popular retail default.
ranked › row 5 › vendor › has overagefalse
ranked › row 5 › vendor › last checked2026-05-25
ranked › row 5 › vendor › tiers › row 1 › nameStocks Starter
ranked › row 5 › vendor › tiers › row 1 › monthly29
ranked › row 5 › vendor › tiers › row 1 › includes livefalse
ranked › row 5 › vendor › tiers › row 1 › includes optionsfalse
ranked › row 5 › vendor › tiers › row 1 › includes futuresfalse
ranked › row 5 › vendor › tiers › row 1 › resolutions › row 1daily
ranked › row 5 › vendor › tiers › row 1 › resolutions › row 2minute
ranked › row 5 › vendor › tiers › row 1 › notes › row 115-min delayed market data
ranked › row 5 › vendor › tiers › row 1 › notes › row 25 calls/min
ranked › row 5 › vendor › tiers › row 2 › nameStocks Developer
ranked › row 5 › vendor › tiers › row 2 › monthly79
ranked › row 5 › vendor › tiers › row 2 › includes livefalse
ranked › row 5 › vendor › tiers › row 2 › includes optionsfalse
ranked › row 5 › vendor › tiers › row 2 › includes futuresfalse
ranked › row 5 › vendor › tiers › row 2 › resolutions › row 1daily
ranked › row 5 › vendor › tiers › row 2 › resolutions › row 2minute
ranked › row 5 › vendor › tiers › row 2 › resolutions › row 3second
ranked › row 5 › vendor › tiers › row 2 › notes › row 115-min delayed
ranked › row 5 › vendor › tiers › row 2 › notes › row 2Unlimited API calls
ranked › row 5 › vendor › tiers › row 3 › nameStocks Advanced
ranked › row 5 › vendor › tiers › row 3 › monthly199
ranked › row 5 › vendor › tiers › row 3 › includes livetrue
ranked › row 5 › vendor › tiers › row 3 › includes optionsfalse
ranked › row 5 › vendor › tiers › row 3 › includes futuresfalse
ranked › row 5 › vendor › tiers › row 3 › resolutions › row 1daily
ranked › row 5 › vendor › tiers › row 3 › resolutions › row 2minute
ranked › row 5 › vendor › tiers › row 3 › resolutions › row 3second
ranked › row 5 › vendor › tiers › row 3 › resolutions › row 4tick
ranked › row 5 › vendor › tiers › row 3 › notes › row 1Full real-time
ranked › row 5 › vendor › tiers › row 3 › notes › row 2Unlimited API calls
ranked › row 5 › tier › nameStocks Starter
ranked › row 5 › tier › monthly29
ranked › row 5 › tier › includes livefalse
ranked › row 5 › tier › includes optionsfalse
ranked › row 5 › tier › includes futuresfalse
ranked › row 5 › tier › resolutions › row 1daily
ranked › row 5 › tier › resolutions › row 2minute
ranked › row 5 › tier › notes › row 115-min delayed market data
ranked › row 5 › tier › notes › row 25 calls/min
ranked › row 5 › monthly29
ranked › row 5 › one time0
ranked › row 5 › annual total348
ranked › row 5 › meets resolutiontrue
ranked › row 5 › meets livetrue
ranked › row 5 › meets optionstrue
ranked › row 5 › meets futurestrue
ranked › row 5 › meets alltrue
ranked › row 6 › vendor › idalpha-vantage
ranked › row 6 › vendor › nameAlpha Vantage
ranked › row 6 › vendor › urlhttps://www.alphavantage.co
ranked › row 6 › vendor › short pitchBudget tier with broad coverage. Rate limits tight. Workable for low-frequency research.
ranked › row 6 › vendor › has overagefalse
ranked › row 6 › vendor › last checked2026-05-25
ranked › row 6 › vendor › tiers › row 1 › namePremium 75
ranked › row 6 › vendor › tiers › row 1 › monthly49.99
ranked › row 6 › vendor › tiers › row 1 › includes livefalse
ranked › row 6 › vendor › tiers › row 1 › includes optionsfalse
ranked › row 6 › vendor › tiers › row 1 › includes futuresfalse
ranked › row 6 › vendor › tiers › row 1 › resolutions › row 1daily
ranked › row 6 › vendor › tiers › row 1 › resolutions › row 2minute
ranked › row 6 › vendor › tiers › row 1 › notes › row 175 calls/min, no daily limit
ranked › row 6 › vendor › tiers › row 1 › notes › row 2Free key capped at 25 calls/day, 5/min
ranked › row 6 › vendor › tiers › row 2 › namePremium 1200
ranked › row 6 › vendor › tiers › row 2 › monthly249.99
ranked › row 6 › vendor › tiers › row 2 › includes livefalse
ranked › row 6 › vendor › tiers › row 2 › includes optionsfalse
ranked › row 6 › vendor › tiers › row 2 › includes futuresfalse
ranked › row 6 › vendor › tiers › row 2 › resolutions › row 1daily
ranked › row 6 › vendor › tiers › row 2 › resolutions › row 2minute
ranked › row 6 › vendor › tiers › row 2 › resolutions › row 3second
ranked › row 6 › vendor › tiers › row 2 › notes › row 11,200 calls/min, no daily limit
ranked › row 6 › vendor › tiers › row 2 › notes › row 2Rate-tiered ladder: $99.99/150, $149.99/300, $199.99/600, $249.99/1200
ranked › row 6 › tier › namePremium 75
ranked › row 6 › tier › monthly49.99
ranked › row 6 › tier › includes livefalse
ranked › row 6 › tier › includes optionsfalse
ranked › row 6 › tier › includes futuresfalse
ranked › row 6 › tier › resolutions › row 1daily
ranked › row 6 › tier › resolutions › row 2minute
ranked › row 6 › tier › notes › row 175 calls/min, no daily limit
ranked › row 6 › tier › notes › row 2Free key capped at 25 calls/day, 5/min
ranked › row 6 › monthly50
ranked › row 6 › one time0
ranked › row 6 › annual total600
ranked › row 6 › meets resolutiontrue
ranked › row 6 › meets livetrue
ranked › row 6 › meets optionstrue
ranked › row 6 › meets futurestrue
ranked › row 6 › meets alltrue

Computed live at build time.

Frequently asked questions

What is the cheapest real-time stock API in 2026?
Alpaca's free IEX feed is $0 and real-time, but IEX is a small share of consolidated volume. For the full SIP tape, the cheapest is Alpaca Algo Trader Plus at $99/mo; Polygon Advanced is $199/mo (verified 2026-05-25).
Is there a free stock market data API?
Yes, several. Alpaca's IEX feed and Polygon's Basic tier are $0; Finnhub's free tier gives 60 calls/min with real-time US quotes. Each has a caveat: volume share, end-of-day-only, or personal-use restriction.
Which free tier has the best rate limit?
Finnhub at 60 calls/minute, versus Alpaca's 200 trading-API limit and Polygon's 5 calls/minute on the free Basic tier.
Cheapest API with fundamentals?
Tiingo's low entry tier (around $10/mo in the engine snapshot, fundamentals on the Power tier). Confirm current pricing on Tiingo's page.