Head to head · Market fundamentals · October 2026 research run

Financial Datasets vs Twelve Data

Twelve Data scores 70 (BB) on agent readiness against Financial Datasets's 61.8 (C), and leads in 6 of 7 scored categories. Financial Datasets leads on payments & pricing. Both do market fundamentals. Financial Datasets accepts x402. Twelve Data doesn't.

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

Which one, for what

Financial Datasets C

Best for An agent doing US company research from SEC-sourced statements, filings, insider and institutional data that wants to pay per call with no account, or a small team on credits.

Ahead on

  • Payments & pricing, 75 against 30

Also in its favour

  • An agent can pay per call over x402, with no account

Watch for

No status page, incident history or published uptime; the Professional plan's SLA terms aren't public

Twelve Data BB

Best for Agents that need prices and time series across many exchanges and asset classes with one contract, CSV output, and a documented error table.

Ahead on

  • Reliability, 83 against 43
  • Agent ergonomics, 84 against 73
  • Security & auth, 54 against 49
  • Maintenance & community, 82 against 56

Also in its favour

  • Agent-ready, a grade of BB or better
  • Runs on your own machine
  • Free to start without a card

Watch for

The REST docs and OpenAPI accept the key as ?apikey= in the query string 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.

Payments & pricing Financial Datasets +45

Financial Datasets 75

x402 on the vendor's own endpoints for every documented GET data endpoint, 36 of them, with the last 365 days only and a Non-Professional licence; full history, the market snapshot, filing items and the POST endpoints need a key (35 of 40). Plan prices and overage rates are public, and each x402 endpoint quotes its price in the 402 header, $0.02 on /earnings (20). No free tier or trial found; data calls return 402 until an account holds credits, from $20 (0). An agent can pay by x402 with no account, or open an account with POST /agent/signup and have the owner fund it (20). Total 75.

Twelve Data 30

No x402, MPP or L402 (0). Plan prices are public without login in pricing.md and on the pricing page, sold by credits a minute per month rather than per call (10). A free Basic plan at 800 credits a day with no card (20). The key comes from a browser signup and no key API was found; MCP needs an OAuth login by a person (0). 0 + 10 + 20 + 0 = 30.

Reliability Twelve Data +40

Financial Datasets 43

Graded as a hosted service. No status page was found; status.financialdatasets.ai does not resolve and no page links one (0), so there is no incident history to read (5). The only published limit is 10,000 requests a minute per wallet over x402, with monthly request caps per plan and none per minute for keyed plans (8 of 15). The OpenAPI file declares 429 and the x402 page documents a 503 with Retry-After from the facilitator and a duplicate_payment check on replayed signatures (10 of 15). The Professional plan lists uptime SLAs, with no figure published (10). The API is generally available (10). Total 43.

Twelve Data 83

Read with the hosted lines. A public status page at twelvedata.isitup.cloud lists Price API, Fundamentals API, WebSocket and Website with uptime figures (20). Its history shows two incidents in the 90 days to 3 November 2026, 20 minutes of unavailability across the three APIs on 1 September and 16 minutes on the WebSocket on 14 October, minor only (20). Limits are published with numbers, credits a minute by plan from 8 to 10,946 and 800 a day on Basic (15). The docs document a 429 on the limit and the usage endpoint, with no Retry-After or backoff guidance; reads only (8 of 15). The terms sell a 99.9 per cent SLA with service credits, and the Enterprise plan carries 99.99 per cent (10). The REST API and MCP server are generally available (10). 20 + 20 + 15 + 8 + 10 + 10 = 83.

Maintenance & community Twelve Data +26

Financial Datasets 56

UK fundamentals went live on 26 October 2026, India on 23 October, with Japan and South Korea dated for November on the coverage page (30). Dated changes in the last 90 days are x402 on 23 October, UK fundamentals on 26 October, terms and subprocessor list on 29 October, privacy policy on 20 August, with no changelog as such (12 of 20). Contact is a form and the dashboard; no support email, Discord or forum was found, and the GitHub organisation's four repositories couldn't be read because the GitHub API rate limit was reached (6 of 15). The PyPI package is 0.1.18 of 26 May 2024 by the founder, and the docs point to the OpenAPI file and the MCP server rather than an SDK (5 of 15). Package health unknown, dependencies not checked (3 of 10). Total 56.

Twelve Data 82

Read as a closed service. The newest dated change is the product update of 12 October 2026, with the MCP repository changed on 1 October and the world-model dataset repository on 31 October (30). Monthly updates dated 12 August, 12 September and 12 October 2026 (20). A monthly changelog, a support portal, a sales contact and a Telegram channel; replies on the MCP repository's issues were not read (10 of 15). Six official SDKs and a CLI, twelvedata-python at v1.4.0 of 27 April 2026 (15). The MCP server pins its dependencies with reasons and ships tests; the Python SDK's changelog stops at version 0.1 (7 of 10). 30 + 20 + 10 + 15 + 7 = 82.

Agent ergonomics Twelve Data +11

Financial Datasets 73

limit and period on the data endpoints, as_reported flags and snapshot variants, with no field selection (15 of 25). next_page_url cursors and ticker, CIK, market and date filters (18 of 20). A 402 body says what to do next, x402 errors carry named values, and the spec lists 400, 401, 403, 404, 409, 422, 429, 502 and 503 (16 of 20). Data calls are GETs, payment settles only after a successful response, and a replayed x402 signature is refused; no readOnlyHint found for the MCP tools and no idempotency key for the POST endpoints (14 of 20). Few required parameters, 28 compact MCP tools, but the only package, financial-datasets on PyPI, is at 0.1.18 from 26 May 2024 (10 of 15). Total 73.

Twelve Data 84

The REST API is the surface graded. outputsize 1 to 5,000 with a default of 30, format=CSV, dp, date ranges and batch requests size responses, and the MCP server lists 27 tools (20 of 25). Date ranges, outputsize and exchange, country and type filters, with no cursor pagination (15 of 20). Error codes with meanings an agent can branch on, 403 for plan limits and 429 for credits (16 of 20). Every operation is a read, and the MCP source marks tools readOnlyHint (18 of 20). Few required parameters, a demo key, and official SDKs in Python, Node.js, Go, Java and R (15). 20 + 15 + 16 + 18 + 15 = 84.

Security & auth Twelve Data +5

Financial Datasets 49

A plain account key in the X-API-KEY header only, revoked from the dashboard, with no scopes, rotation or expiry; the MCP server adds OAuth 2 with PKCE (plain and S256), dynamic client registration, a revocation endpoint and one scope (20 of 30). Every data endpoint is a read; the x402 route and agent signup don't change the account beyond funding it (15 of 20). Filing text, filing items and news are third-party content, with no guidance on treating them as untrusted (5 of 15). The privacy policy says requests and responses are logged for up to three years; no per-call log is shown to the key holder (5 of 15). security.txt returns 404 and no bounty, SOC 2 or ISO 27001 was found; the terms ask for prompt notice of a compromised key and a subprocessor list is published (4 of 20). Total 49.

Twelve Data 54

The REST key is a plain per-account key with no scopes, accepted as a header or as ?apikey= (20 less 10 for the query string). The hosted MCP server refuses keys and uses OAuth 2.1 with PKCE, a resource indicator, refresh tokens, revocation and one scope, which lifts the credential model for that surface (18 of 30). Every operation is a read (15 of 20). Company news is third-party text and no guidance was found (5 of 15). An /api_usage endpoint and dashboard usage give the key holder a view of consumption, not a per-call log (6 of 15). A trust centre on SafeBase lists SOC 2, GDPR and CCPA and ten policies; no security.txt, disclosure process or bug bounty was found (10 of 20). 18 + 15 + 5 + 6 + 10 = 54.

Score by category

CategoryWeight this runFinancial DatasetsTwelve DataEdge
Reliability16%204383Twelve Data +40
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28083Twelve Data +3
Agent ergonomics13%16.27384Twelve Data +11
Security & auth14%17.54954Twelve Data +5
Payments & pricing10%12.57530Financial Datasets +45
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.85682Twelve Data +26
Transparency & trust7%8.86367Twelve Data +4
Negative events≤1500
TotalC 61.8/100BB 70/100

Facts side by side

FactFinancial DatasetsTwelve Data
KindHTTP APIHTTP API
VendorFinancial Datasets, Inc.Twelve Data Pte. Ltd.
Hosted endpointhttps://api.financialdatasets.aihttps://api.twelvedata.com
TransportsHTTP, Streamable HTTPHTTP, Streamable HTTP, stdio, websocket
AuthOAuth or keyOAuth or key
PricingPay per useFreemium
x402yes, from $0.02/callno
Tools exposed2827
Read-only variant documentednoyes
llms.txtyesyes
Last release2026-10-262026-10-12
Terms last updated2026-10-292026-01-01
Privacy policy last updated2026-08-202026-09-22
Customer content may train modelsnot found in the textnot found in the text
Terms restrict automated accessyesnot found in the text
Terms restrict benchmarkingyesyes
Terms or service can change without noticenot found in the textyes
Arbitration or class-action waivernot found in the textyes
Popularitynone791 stars

Verdicts

Financial Datasets

Every documented GET data endpoint takes x402 with no key, failed calls uncharged, and an agent can open and fund an account by API. A public OpenAPI file, llms.txt and a 28-tool OAuth MCP server cover the same data. There is no status page or free tier, keyed rate limits aren't published, and x402 data stops at 365 days.

Twelve Data

A public OpenAPI 3.1 document with error responses on all 187 operations, Markdown docs and pricing for agents, a status page with two short incidents in 90 days, and an MCP server behind OAuth 2.1. The REST key still travels in the query string as a documented option, no enums are declared, and free and individual plans forbid company use.

Before you call either

Financial Datasets

  1. Without a key, read the price from the PAYMENT-REQUIRED header of the 402 and pay with x402 on Base; each page of next_page_url is a separate paid request
  2. Keep limit small and ask for one period at a time; premium endpoints count as 2, 4 or 8 requests on keyed plans
  3. Send the key only to api.financialdatasets.ai in the X-API-KEY header; on 401 ask the owner for a new key rather than signing up again
  4. Treat a 402 on a keyed account as an empty balance and mint a checkout link for the owner; don't retry the call
  5. Check the plan's licence before showing the data to anyone else; redistribution needs Professional or Enterprise

Twelve Data

  1. Send the key as Authorization: apikey <key>, not in the URL; the hosted MCP server takes OAuth only, so never paste a key into a connector's key field
  2. Set outputsize (1 to 5,000, default 30) and format=CSV on time_series to keep responses small, and read status in the JSON body since errors come with HTTP codes and a message
  3. Count credits, not calls; most endpoints cost one credit per symbol and the Basic plan allows 8 a minute and 800 a day, with 429 when exceeded
  4. A 403 means the key's plan lacks the endpoint or symbol, not a bad key; check pricing.md before escalating
  5. Use trial symbols from twelvedata.com/exchanges to test premium data on the free plan

Questions

Which is better for AI agents, Financial Datasets or Twelve Data?

Twelve Data scores 70 (BB) on agent readiness against Financial Datasets's 61.8 (C), and leads in 6 of 7 scored categories. Financial Datasets leads on payments & pricing.

Do Financial Datasets and Twelve Data need an API key?

Both take an API key or an OAuth sign-in. An agent can also pay Financial Datasets per call over x402, with no account.

Can an agent call Financial Datasets and Twelve Data without installing anything?

Yes. Financial Datasets has a hosted endpoint at https://api.financialdatasets.ai and Twelve Data at https://api.twelvedata.com.

Other comparisons with Financial Datasets or Twelve Data

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