Alpaca
Commission-free stock trading API for developers and algorithms.
Open the official app on alpaca.markets
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Use it free
Open the official tool or demo — no account needed.
Self-host it
Run the open-source version on your own infrastructure.
What is Alpaca?
Alpaca is an open-source financial API platform designed to enable developers and businesses to integrate trading capabilities for stocks, options, and cryptocurrencies into their applications and services. Its primary purpose is to provide programmatic access to real-time market data, order execution, and portfolio management tools, allowing users to build algorithmic trading systems, financial apps, and embedded investing features. Developers, fintech startups, and institutional traders leverage Alpaca to streamline access to financial markets, reduce infrastructure costs, and innovate around trading algorithms without needing to develop proprietary trading infrastructure. The tool addresses the challenge of connecting diverse financial instruments with customizable APIs, offering a unified interface for executing trades, managing accounts, and accessing market data across multiple asset classes.
How it works
Alpaca serves as a developer-first API toolkit for accessing stock, options, and crypto markets. It enables programmatic trading, market data retrieval, and portfolio management through RESTful endpoints and WebSocket connections, catering to both individual traders and institutional clients. The platform's core purpose is to democratize access to financial markets by abstracting complex trading mechanics into simple API calls. It supports features like real-time price feeds, order execution, and account balance tracking, users to build custom trading solutions without deep market infrastructure knowledge. Alpaca provides APIs for executing trades in stocks, options, and cryptocurrencies, along with tools for backtesting strategies and managing account portfolios. It supports multi-leg options strategies, such as spreads and straddles, and offers high-yield cash accounts with FDIC insurance. The platform also includes an instant tokenization network for trading tokenized equities with 24/7 API access.
How to use it
- 1Register for a free account to obtain API credentials. 2. Use the provided SDKs or REST APIs to connect to market data and trading endpoints. 3. Implement trade logic using WebSocket for real-time updates or REST for batch requests. 4. Monitor account balances and execute trades programmatically through the API. Practical tips include leveraging the High Yield Cash feature for liquidity management, testing strategies with historical data, and ensuring compliance with market regulations when deploying trading algorithms.
What it can do
- trading api
Use cases
Assumptions and limitations
Assumptions
- source: https://alpaca.markets/
- license: Apache-2.0 — free to use
- privacy: Opens an external demo
Limitations
- Limited support for niche markets or exotic derivatives
- Dependence on third-party exchanges for order execution
- Potential latency in high-volume trading scenarios
- Requires API key management and security best practices
- Learning curve for integrating WebSocket and REST endpoints
Understanding the result
Commission-free stock trading API for developers and algorithms.
Tool details
- Clearly flagged when a network request is needed.
- No account, no sign-up, and no tracking of your content.
- Powered by (Apache-2.0).
- Built with
- (https://alpaca.markets/)
- License
- Apache-2.0
- Runs locally
- No — requires a network request
- Verification
- Not yet verified
- Input
- Query
- Output
- Text
Built with https://alpaca.markets/. OpenToolVault provides the discovery and browser interface while crediting the original project maintainers.
- Built with
- License
- Apache-2.0
Open-source project
OpenToolVault is an independent directory. We are not affiliated with or endorsed by this project.
References
- / — GitHub Repository
Upstream project · GitHub
- Apache-2.0 License
Upstream project
Frequently asked
What is Alpaca and what does it do?
Alpaca is an open-source API platform for accessing stock, options, and crypto markets. It allows developers to build trading applications, embed financial tools into services, and execute trades programmatically. Its core features include real-time market data access, order execution, and portfolio management via RESTful APIs and WebSockets.
How does Alpaca's API handle market data and trade execution?
Alpaca's API uses REST endpoints for structured data retrieval and trade execution, while WebSockets provide real-time updates for market prices and order book data. The platform connects to multiple exchanges to execute trades, though users must ensure compliance with exchange-specific rules and latency constraints.
How do I start using Alpaca's API for trading?
First, sign up for a free account to get API keys. Next, use the provided SDKs (e.g., Python, Node.js) or make HTTP requests to the REST API endpoints. Implement trade logic by sending POST requests to the trade endpoint, then monitor account balances via the account API. For real-time data, subscribe to WebSocket streams for price updates.
How does Alpaca compare to alternatives like Interactive Brokers or Alpaca Trading API?
Alpaca focuses on developer-friendly APIs and open-source integration, while Interactive Brokers offers more advanced order types and market access. The Alpaca Trading API is a subset of the broader platform, prioritizing simplicity for app developers. Both tools require API key management, but Alpaca emphasizes ease of embedding into third-party services.
What should I do if I get an API rate limit error?
Rate limit errors occur when exceeding the allowed number of API requests. To resolve this, check the API documentation for rate limits, implement request throttling in your code, and use asynchronous requests where possible. Monitor usage through the dashboard and upgrade to a premium plan if higher throughput is needed.