Or just quit being cheap and fork over a very small amount of money for live data. You get free access to the api on ibkr if you make $20 of trades per month. There are other cheap options too. It’s honestly not worth the time you’re wasting looking for “free” More on reddit.com

Hi there, I design financial-based web apps that perform all kinds of stock market functions and analysis. My first question is, what do you want to build and why? Would you like to monetize your work somehow via advertising or subscriptions, etc.? I only ask because unless you are using stock data on your own computer and not making it available to others via an app or a website, you are really not going to find anything legally for free. I pay for several services and I can say that the biggest advantage to that is that you can rely on your data to be working most all of the time. If you are using a free "hack" you never know when everything will just shut off and if you need reliability, you should really pay for a feed. Anyway, hit me up if you want to chat about your project, goals and so forth. I've helped numerous people over the years set up their own, customized SaaS businesses revolving around financial dashboards, etc. Cheers! More on reddit.com

[FREE] Alpaca Markets - haven't tried it yet, but it's free, REST API, looks cool, has only stocks, haven't seen options or futures [FREE] RobinHood - you can find implementation of intercepted RobinHood API on GitHub, it's also free, REST API, but RH can ban you for using it, because they can barely handle load from manual traders, you can trade options for free IEX Exchange - it was free for non-profit organizations, brokers, and other exchanges, now it's available to retail traders for something like $5-$10 a month, only stocks, maybe currencies, no options or futures Interactive Brokers - so-o-o-o-o-o sl-o-o-o-o-w, it's ok to use it if you want to trade stocks, but getting options chain for only one single week takes minimum 30 seconds after all code optimizations, initial implementation took something around 5 minutes, if you have an account in IB, you only need to buy subscriptions to specific market data, aPI is free and kind of open-source, available on GitHub if you send them a request to add you to GitHub repository TD Ameritrade - works much much faster than IB, like milliseconds compared to minutes, has REST API for all kind of securities, but people say their API is still in beta mode, and Schwab is going to buy TDA soon, so some features, like API may be abandoned LightSpeed - they seem to have C++ and C# API, but it's attached to their platform, so you have to pay $300-$500 a month only to get their platform first [FREE] Meta Trader 5 - US stocks can be traded through Just 2 Trade - Finam, futures can be traded through AMP Futures, no options, API is free, but you have to create your own bridge between your program and MT5 Quant Connect - stocks, options, and currencies, C# and Python API libraries, free for testing on historical data and $20 for real-time trading through IB gateway. IQ feed - perhaps the fastest way to get market data for options, but you still need a broker to send actual orders to buy or sell, costs around $50 a month More on reddit.com

I like Tradier. If you want “big boy” data, databento has it all. You can find industry classifications online for free, somebody has a github that they update nightly with all traded US stocks and their fundamental. More on reddit.com