Head to head · Market fundamentals · October 2026 research run

Financial Modeling Prep vs Tiingo

Financial Modeling Prep scores 48.7 (D) on agent readiness against Tiingo's 46.2 (D), and leads in 3 of 7 scored categories. Tiingo leads on reliability. Both do market fundamentals.

Best financial market data APIs for AI agents · All 55 markets comparisons

Which one, for what

Financial Modeling Prep D

Best for Agents doing company research on statements, ratios, DCF, filings, transcripts and calendars with one key, and US coverage on cheap plans.

Ahead on

  • Schema & documentation, 61 against 39
  • Maintenance & community, 60 against 50

Also in its favour

  • Free to start without a card

Watch for

The documented MCP connection URL puts the API key in the query string, and the REST docs accept ?apikey= too

Tiingo D

Best for Agents that need clean US end-of-day composites with dividend and split adjustments, fund fees and news on a cheap plan, and anyone who values a long changelog.

Ahead on

  • Reliability, 60 against 50

Watch for

The connecting guide documents the token as ?token= in the URL alongside the header

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Schema & documentation Financial Modeling Prep +22

Financial Modeling Prep 61

No OpenAPI document was found. The MCP page says the server supplies strict parameter definitions, but the tool list needs a key and was not read (5 of 25). llms.txt links api-docs.md and pricing.md, Markdown written for agents (10). Each of the 199 endpoints in api-docs.md has a purpose paragraph and a plan marker in pricing.md, with little on when not to use it (13 of 20). Parameters are tabled with type, example and a required star, but allowed values sit in prose and no enums are given (8 of 15). Every endpoint has an example request and response; no error responses are documented anywhere we read (10 of 15). A /stable path, legacy /v3 and /v4 marked discontinued, and a changelog dated by day through 2 November 2026 (15). 5 + 10 + 13 + 8 + 10 + 15 = 61.

Tiingo 39

No OpenAPI document or MCP server was found (0 of 25). llms.txt and llms-full.txt are served, with product routing and licence notes (10). Each documentation page states the endpoint's purpose and timing, such as prices after 5.30 pm ET with corrections to 8 pm, with little on when not to use it (12 of 20). Parameters and response fields are tabled with names and meanings, but types, defaults and allowed values are partly in prose (8 of 15). Examples in Python, Node and PHP on every page; no error responses documented (7 of 15). A changelog dated by entry since 2017 and a one-year support commitment after breaking changes, with no version in the path (12 of 15). 0 + 10 + 12 + 8 + 7 + 12 = 39.

Reliability Tiingo +10

Financial Modeling Prep 50

Read with the hosted lines. A public status page at status.financialmodelingprep.com is linked from every page (20), but its figures load by script and our reader got an error, so no incident history could be read (5). Limits are published with numbers, 250 calls a day on Basic and 300, 750 and 3,000 calls a minute on paid plans, with bandwidth caps per plan (15). No 429 behaviour, Retry-After or backoff guidance was found in the docs, api-docs.md or FAQs (0). No SLA found; the terms let FMP change limits without notice (0). The stable API is generally available (10). 20 + 5 + 15 + 0 + 0 + 10 = 50.

Tiingo 60

Read with the hosted lines. A public status page on Instatus at status.tiingo.com lists 13 components with a notice history (20). The history in the 90 days to 3 November 2026 shows a 9 hour 59 minute outage of the Blue Ocean ATS endpoints on 21 October, a WebSocket issue on 21 September and two maintenance windows, with nothing recorded before 21 September; a long outage of one niche feed rather than the core price API (15). Limits are published with numbers, 50 and 10,000 requests an hour, 1,000 and 100,000 a day and 1 GB and 40 GB a month (15). No 429, Retry-After or backoff guidance was found (0). No SLA found (0). The end-of-day, news, crypto and forex APIs are generally available, while Equity Realtime and BOATS are in beta (10). 20 + 15 + 15 + 0 + 0 + 10 = 60.

Maintenance & community Financial Modeling Prep +10

Financial Modeling Prep 60

Read as a closed service. The changelog's newest entry is 2 November 2026 (30). Entries dated 6, 8, 12, 28 and 29 October and 2 November 2026, more than three in 90 days (20). A public changelog, a help centre, FAQs and a support address, with issues reported through a site chatbot per the FAQ (10 of 15). No official SDK; the FAQ points at third-party packages (0 of 15). No package to assess, and nothing else to show for CI or dependency health (0 of 10). 30 + 20 + 10 + 0 + 0 = 60.

Tiingo 50

Read as a closed service. The changelog's newest entry is 9 October 2026 (30). Entries dated 9 October and 8 September 2026 fall in the last 90 days, with 21 July just outside, and the status page adds a maintenance window on 28 September (12 of 20). A dated changelog, a support address and a blog, with the developer programme promising priority email support (8 of 15). No official SDK (0 of 15). No package to assess (0 of 10). 30 + 12 + 8 + 0 + 0 = 50.

Score by category

CategoryWeight this runFinancial Modeling PrepTiingoEdge
Reliability16%205060Tiingo +10
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26139Financial Modeling Prep +22
Agent ergonomics13%16.25956Financial Modeling Prep +3
Security & auth14%17.53032Tiingo +2
Payments & pricing10%12.53030even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.86050Financial Modeling Prep +10
Transparency & trust7%8.85757even
Negative events≤1500
TotalD 48.7/100D 46.2/100

Facts side by side

FactFinancial Modeling PrepTiingo
KindHTTP APIHTTP API
VendorFinancial Modeling PrepTiingo Inc.
Hosted endpointhttps://financialmodelingprep.com/stablehttps://api.tiingo.com
TransportsHTTP, Streamable HTTPHTTP, websocket
AuthAPI keyAPI key
PricingFreemiumFreemium
x402nono
Read-only variant documentednono
llms.txtyesyes
Last release2026-11-022026-10-09
Terms last updatedcouldn't be readcouldn't be read
Privacy policy last updatedcouldn't be read2026-02-18
Customer content may train modelscouldn't be readcouldn't be read
Terms restrict automated accesscouldn't be readcouldn't be read
Terms restrict benchmarkingcouldn't be readcouldn't be read
Terms or service can change without noticecouldn't be readcouldn't be read
Arbitration or class-action waivercouldn't be readcouldn't be read

Verdicts

Financial Modeling Prep

About 199 stable REST endpoints with Markdown docs for agents, a dated changelog and a free key at 250 calls a day. The one key travels in the query string on the documented MCP address, error responses and 429 handling are undocumented, the status history could not be read, and personal plans forbid any company use.

Tiingo

A dated changelog since 2017, a one-year support commitment after breaking changes, an Instatus status page and a free token at 1,000 requests a day. The token is documented in the URL, no OpenAPI document, error reference, SDK or MCP server exists, and the terms and privacy policy sit on a host that refused our reader.

Before you call either

Financial Modeling Prep

  1. Send the key as an apikey header, not in the URL, and treat the MCP ?apikey= address as a secret
  2. Use the /stable paths from api-docs.md; /api/v3 and /v4 are discontinued even though the FAQ still shows a v3 example
  3. On the free plan expect 5 results and page 0 on many list endpoints; read pricing.md before planning a crawl
  4. A missing or wrong key returns HTTP 401 with an Error Message field; stop and ask the user rather than retry
  5. Do not display or pass on the data in a product; personal plans forbid it

Tiingo

  1. Send the token as Authorization: Token <token>, not as ?token= in the URL
  2. Ask for format=csv on large price pulls; the docs say CSV is 4 to 5 times faster than JSON, and bandwidth counts against the monthly cap
  3. Count requests an hour and a day, not per second; 50 an hour on Starter, 10,000 on Power, reset on the hour and at midnight ET
  4. Expect 403 {"detail":"Please supply a token"} without a token; other error shapes are undocumented, so log the body
  5. Use dashes in share classes (BRK-A), and fetch supported_tickers.zip rather than guessing symbols

Questions

Which is better for AI agents, Financial Modeling Prep or Tiingo?

Financial Modeling Prep scores 48.7 (D) on agent readiness against Tiingo's 46.2 (D), and leads in 3 of 7 scored categories. Tiingo leads on reliability.

Do Financial Modeling Prep and Tiingo need an API key?

Both need an API key.

Can an agent call Financial Modeling Prep and Tiingo without installing anything?

Yes. Financial Modeling Prep has a hosted endpoint at https://financialmodelingprep.com/stable and Tiingo at https://api.tiingo.com.

Other comparisons with Financial Modeling Prep or Tiingo

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