Yahoo Finance? I remember using them a lot with some R packages a while back. Also as @rohan_talip said, IB is a good option and also check this Github repo for a finviz unofficial api https://github.com/mariostoev/fi... hope those help
Hi Mike, have you looked at Interactive Brokers' API? I was investigating it myself a while back but I haven't used it yet. See https://www.strategic-options.co... for a comparison with a couple of other APIs.
What exactly are you looking for? I’ve build applications that pull real-time market data and company information using https://iexcloud.io/. Quandl also has a ton of useful data, the probably most accurate for historical closing prices: https://www.quandl.com/data/EOD-...
There’s also https://alpaca.markets/ that is an API-only brokerage.
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