ExchangeRate-API.com offers an easy-to-use JSON currency conversion API with unlimited free requests. The service supports all 160 major currency codes and an incredibly accessible API request format. ExchangeRate-API has been a popular option for developers to get exchange rate data since 2010!
Gurufocus - Historical financial data and insider holdings
Fixer.io - Fixer provides a free, simple, and lightweight API for current and historical foreign exchange rates and currency conversion. The API tracks rates published daily by the European Central Bank.
Smartfin - Experience a fast & easy way to research companies, with 30+ years of financial data, key metrics, and insights for humans. Build watchlists, track updates, and stay ahead with real-time alerts, earnings reports, and more!
exchangeratesapi.io - Foreign exchange rates API with currency conversion.
FinChat - Your AI powered stock investing analyst
Open Exchange Rates - Free, hourly-updated exchange rates - a simple, accurate, open-source JSON API. Free for personal use, a bargain for everybody else.