Sign up, copy your API key from the dashboard, then call GET /api/etf/list?search=SPY with the x-api-key header.

Stock market API

US stock market data API built for product teams

Data Captain gives developers a single API key for US ETF market data — latest prices, searchable universe, market status, and production-ready rate limits.

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Key endpoints

GET/api/etf/list
Searchable ETF universe
GET/api/stocks/prices
Batch latest prices
GET/api/market/status
US market open/closed
GET/api/stocks/:symbol/price
Single-symbol quote

Why teams use Data Captain

One key, REST JSON

Authenticate with x-api-key. Responses are predictable JSON — ideal for React, Next.js, and backend workers.

ETF-first market coverage

Production coverage focuses on US-listed ETFs with loaded historical prices (SPY, QQQ, VOO, and thousands more).

Free tier to ship a prototype

Validate auth, latency, and response shape before upgrading for history, backtests, and higher daily limits.

Common use cases

Investment dashboards and watchlists
Fintech MVP market-data backends
Portfolio and research tools
Educational and content products with live examples

FAQ

Is Data Captain a full US equities stock API?

Data Captain is optimized for US ETF market data. Paths under /api/stocks work with ETF symbols that have price history in our database. Prefer /api/etf endpoints for universe search and screener workflows.

How do I start?

Historical stock API →Stock screener API →Best ETF APIs guide →

Ship a market-data prototype this week

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