# Best financial market data APIs for AI agents (slim)

> Massive (formerly Polygon.io) (BB), Twelve Data (BB) and Financial Datasets (C) lead the 11 ranked financial market data APIs. Picks by need, strengths, weaknesses and prices from the Anchor benchmark.

- Full: https://www.anchorterminal.com/best/market-data/index.md (~6,500 tokens) · this version ~1,580 tokens · JSON https://www.anchorterminal.com/best/market-data/index.json · canonical https://www.anchorterminal.com/best/market-data/
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-11-03
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)

The 10 highest-scoring of 11 financial market data APIs on the Anchor benchmark, with a pick for each need and where each one falls short. Scores come from public evidence, re-checked as vendors change.

- Ranked: 11 · agent-ready (BB or better): 2 · accept x402: 2 · hosted endpoints: 11
- Full ranked table: https://www.anchorterminal.com/categories/market-data.md
- Head-to-head comparisons: https://www.anchorterminal.com/compare/market-data/index.md (55)
- Methodology: https://www.anchorterminal.com/benchmark/index.md

## The shortlist

| # | Tool | Grade | Score | Best for | Price | Where |
| --- | --- | --- | --- | --- | --- | --- |
| 1 | [Massive (formerly Polygon.io)](https://www.anchorterminal.com/tools/massive.md) | BB | 73.1 | Agents that need US equities, options or futures data with real history, and the only listing here selling US stock data over x402. | $0.01 / call | Hosted |
| 2 | [Twelve Data](https://www.anchorterminal.com/tools/twelve-data.md) | BB | 70 | Agents that need prices and time series across many exchanges and asset classes with one contract, CSV output, and a documented error table. | $29 / mo | Hosted and local |
| 3 | [Financial Datasets](https://www.anchorterminal.com/tools/financial-datasets.md) | C | 61.8 | 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. | $0.02 / call | Hosted |
| 4 | [Databento](https://www.anchorterminal.com/tools/databento.md) | C | 60.3 | An agent that needs exchange-level trades, quotes, order book and bar data for US and European futures, options and equities, or corporate actions and a security master, and can budget per GB. | $199 / mo | Hosted |
| 5 | [EODHD](https://www.anchorterminal.com/tools/eodhd.md) | C | 59 | Agents that need long end-of-day history, dividends and splits and fundamentals across 60 exchanges at a low monthly price, with weighted calls to budget. | $19.99 / mo | Hosted and local |
| 6 | [Intrinio](https://www.anchorterminal.com/tools/intrinio.md) | C | 54.2 | An agent doing US equity, options and fundamentals research on a paid plan that wants one vendor for prices, filings, estimates and an OAuth MCP server. | $150 / mo | Hosted |
| 7 | [Benzinga](https://www.anchorterminal.com/tools/benzinga.md) | D | 49.2 | A licensed firm's agent that needs Benzinga's own newswire, calendars, analyst ratings and transcripts as structured data with deltas. | Paid | Hosted |
| 8 | [Financial Modeling Prep](https://www.anchorterminal.com/tools/financial-modeling-prep.md) | D | 48.7 | Agents doing company research on statements, ratios, DCF, filings, transcripts and calendars with one key, and US coverage on cheap plans. | $29 / mo | Hosted |
| 9 | [Tiingo](https://www.anchorterminal.com/tools/tiingo.md) | D | 46.2 | 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. | $30 / mo | Hosted |
| 10 | [Finnhub](https://www.anchorterminal.com/tools/finnhub.md) | E | 45.1 | Agents that need one key across quotes, fundamentals, estimates, filings and transcripts with official libraries, and a free key for prototypes. | $49.99 / mo | Hosted |

## Picks by need

- Highest score overall: [Massive (formerly Polygon.io)](https://www.anchorterminal.com/tools/massive.md), BB, 73.1/100 on the benchmark. Also [Twelve Data](https://www.anchorterminal.com/tools/twelve-data.md), BB, 70/100.
- Reliability: [Twelve Data](https://www.anchorterminal.com/tools/twelve-data.md), 83/100 on reliability, against 78 for the overall leader.
- Agent ergonomics: [Twelve Data](https://www.anchorterminal.com/tools/twelve-data.md), 84/100 on agent ergonomics, against 78 for the overall leader.
- Security & auth: [Databento](https://www.anchorterminal.com/tools/databento.md), 61/100 on security & auth, against 35 for the overall leader.
- Maintenance & community: [Databento](https://www.anchorterminal.com/tools/databento.md), 84/100 on maintenance & community, against 82 for the overall leader.
- Paying per call with no account (x402): [Massive (formerly Polygon.io)](https://www.anchorterminal.com/tools/massive.md), accepts x402, $0.01 a call. Also [Financial Datasets](https://www.anchorterminal.com/tools/financial-datasets.md), accepts x402, $0.02 a call.
- The review panel's favourite: [Alpha Vantage](https://www.anchorterminal.com/tools/alpha-vantage.md), 3/5 from 4 panel reviews.

## How to choose

- Delayed or real time: Check whether quotes are real time, delayed 15 minutes or end of day on the plan the agent will use, since an agent acting on a stale price acts on the wrong one.
- Exchange and asset coverage: Check which exchanges, asset classes and countries the data covers, because many vendors cover US stocks well and the rest thinly.
- Redistribution and display terms: Read whether the licence allows storing, displaying or passing on the data, as exchange data often comes with limits the vendor passes down to each key.
- Free tier limits: Check the calls allowed per minute and per day on a free key, since fundamentals and history calls are often counted differently from quotes.

- How the benchmark tests this category: In this run, public evidence against the published checklist. When the task suites run, the same ten tickers asked of each listing for a year of daily closes, the last four quarterly statements and the most recent filing, the answers checked against the exchange and the regulator. We check coverage, the delay on a live quote, what a free key allows in a day and what the licence lets an agent keep.

Each listing's verdict, strengths and weaknesses: https://www.anchorterminal.com/best/market-data/index.md