Stock market API is arguably the most important part in any trading strategies or financial applications. With a good stock market API, you can reliably backtest your strategy, build a financial website or ?. the next Bloomberg.
In this story, we will discuss the best free and paid stock market API that I?ve found and done research on.
Background knowledge about Stock API
Stock market API provides traders with real-time and historical price across different markets. Some providers also support fundamental and alternative data for deeper analysis or commercial applications.
It?s surprisingly difficult in the 21st century to obtain high-quality financial data for the US, let alone global markets. That?s why many data providers have been working towards breaching this gap for retail investors.
Photo by Austin Distel on Unsplash
Here is a list of Reputable, Free and Affordable options:
- Finnhub.io (Recommended)
- Tiingo (Recommended)
- IEX (Recommended)
- Alpha vantage (Avoid ? unauthorized vendor)
- Worldtradingdata (Shut down)
- Barchart On Demand
- Quandl
- Intrinio
- EODhistoricaldata
More expensive stock api providers :
- IQFeed (Recommended)
- Polygon.io (Avoid)
- Active tick
- Tickdata (Recommended)
1. Finnhub.io
Coverage: Global
Historical data: 25 years intraday data and EOD for US market
Tick data: 25 years
Fundamental data: Global coverage of Company profile, Financial statements, Analyst?s price target and recommendation, News etc.
Alternative data: Earnings call transcript, News sentiment, Merger and Acquisition data
Stock API Access : REST API and Websocket
Pricing : Free plan comes with 60 API calls/minute
Pros: Institutional-grade data with the most generous free plan. Finnhub is the most comprehensive stock API available for retail investors at this point.
Sample code (you can run this code without an API key):
Stock Market API python example:
Tradingview library compatible OHLC result:
{ “c”: [ 217.68, 221.03, 219.89 ], “h”: [ 222.49, 221.5, 220.94 ], “l”: [ 217.19, 217.1402, 218.83 ], “o”: [ 221.03, 218.55, 220 ], “s”: “ok”, “t”: [ 1569297600, 1569384000, 1569470400 ], “v”: [ 33463820, 24018876, 20730608 ]}
2. Tiingo
Coverage: US equity, China equity, forex, crypto
Historical data: 20 years EOD , intraday data
Tick data: Supported via IEX firehose
Fundamental data: US and China coverage.
Alternative data: Not available
Stock API Access : REST API and Firehose from IEX
Pricing : Free plan comes with 500 API calls/hour and 500 unique symbols/month.
Pros: Very affordable. Premium plan only costs $10/month
3. Worldtradingdata
Coverage: Stock API with global markets (60+ stock exchanges) data, forex, crypto
Historical data: 20+ years EOD , 1 month of intraday data
Tick data: Not available
Fundamental data: Not available
Alternative data: Not available
Stock API Access : REST API
Pricing : 250 API calls/DAY
Pros: Reliable system which lets you query up to 500 symbols in 1 API call.
4. IEXcloud
Coverage: US fundamentals and market data for global markets (22+ stock exchanges), forex, crypto
Historical data: 20+ years EOD , 30 days 1 minute data. No support for different OHLC timeframes.
Tick data: Not available
Fundamental data: US coverage of Company profile, Financial statements, Analyst?s price target and recommendation, news, split etc.
Alternative data: Available through 3rd partners (Wall St Horizon, Fraud Factors, Extract Alpha). Sample data: extensive company?s events, same store sales, legal actions, ESG etc.
Stock API Access : REST API and SSE streaming.
Pricing : Message-based system. Free plan come with 50000 messages per month with ?Limited access to Core Data?. This is probably the worst part of IEXcloud as the message-based system is so complicated and you might run out of messages before the month ends and you will have to pay more to continue using the service.
Pros: Reputable IEX exchange with quite comprehensive dataset for US market.
5. Eodhistoricaldata
Coverage: Stock API with global markets (60+ stock exchanges) data, forex, crypto
Historical data: 20+ years EOD , intraday data for 5-minute resolution only. Intraday data is also updated at the end of the day
Tick data: Not available
Fundamental data: Global coverage of Company profile, Financial statements, Analyst?s price target.
Alternative data: Not available
Stock API Access : REST API
Pricing : No free plan. Cheapest plan starts at $19.99/month which gives you 100000 API calls/DAY
Pros: Affordable with comprehensive data
Cons: Data is only updated at the end of the day, including intraday data.
6. Barchart On Demand
Coverage: Stock API with US equity support, futures, forex, crypto
Historical data: 6 months EOD , 1 month intraday data
Tick data: Supported
Fundamental data: US coverage of financial statements and company profile. Not available for free plan
Alternative data: Not available
Stock API Access : REST API
Pricing : Free plan comes with 150 API calls/DAY
7. Quandl and Intrinio
Both companies are marketplace for different data providers and you need to purchase different packages to access their data
Coverage: Mostly US with limited international markets
Historical data: 20+ years EOD , intraday data.
Tick data: Supported.
Fundamental data: US coverage of Company profile, Financial statements, Analyst?s price target and recommendation, News etc.
Alternative data: Only available for institutional clients on Quandl.
Stock API Access : REST API and Websocket
Pricing: Multiple free packages on Quandl however US EOD data free package is not available anymore. Intrinio only offers free trial.
Pros: A lot of choices from different providers.
8. Alpha Vantage
Coverage: Stock API with global markets (60+ stock exchanges) data, forex, crypto
Historical data: 20+ years EOD , 3 weeks of intraday data
Tick data: Not available
Fundamental data: Not available
Alternative data: Not available
Stock API Access : REST API
Pricing : 500 API calls/DAY
Cons:
Beware: Legal action has been taken against this company by multiple exchanges including Nasdaq, TSX, LSE, ASX, NSE. Data is slowly disappearing on Alpha vantage, including NYSE, Nasdaq, ASX, NSE, Nordic exchanges, LSE, TSX etc. US stocks are now end of day only. A response from their support shows that Alpha vantage is not an authorized vendor. . Use their API at your own risk or check with the exchanges before implementing the API.
Confirmation from TSX that Alpha Vantage is an unauthorized vendor. Image obtained from here
Intraday data is limited and their support is virtually non-existent. If you are working on a more serious project, you should consider other options.
More Expensive Stock API Providers
1. Polygon ($199/month)
Polygon is the new kid on the block and their stock API is super easy to use with support for tick data across 16 US exchanges and dark pools. However data quality is very questionable as they constantly get splits and dividends adjusted data wrong. Tick endpoint also returns error from time to time so you might not be able to build your own OHLC data.
Fundamentals: US company financial statements, news and analyst?s recommendations.
Alternative data: Not available
2. Tickdata
High quality data but super expensive. Their pricing model is complicated and can be found here . Basically, it will cost $1638/month to access 3 years of tick data for 20 symbols.
I have seen a lot of complaint about the integration part with Tickdata as they are not user friendly for retail investors. Tickdata only focuses on delivering historical tick data for all asset classes around the world which makes it more suitable for professional and institutional traders.
3. Others
As for the other options, users have been generally happy with their data quality but since their technologies are old, it?s somewhat hard to integrate these services especially on a Linux server.
I will provide more details about these premium options when more information is available.
Wrap Up
I hope that this guide will be the go-to guide for any retail investors who are looking for financial data to either build their own strategies or create the next big financial application. If you have any questions or suggestions, feel free to comment below.
(This story will be actively edited to keep information up to date)
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