Stock screeners feel like something you should have to pay a data vendor for. Market cap, sector, P/E, dividend yield, RSI, daily change, all of it across thousands of tickers, updated through the day. In practice a lot of that is one keyless JSON call away, and you can run it yourself.
Source: [Dev.to](https://dev.to/scrapemint/how-to-screen-thousands-of-stocks-without-a-data-provider-125h)