I really can't say what's the best. It depends on your level of knowledge and what your looking for in a scanner. I have TD(Thinkorswim) due to me having the ability to write my own scripts. Black box and Scanz was my two favorites. However Blackbox ended it's OTC scanner and Scanz charged extra for the OTC settings. That's what lead me to play around with TD scanner. Etrade has one also in Power etrade . However I have not set it up due to, October 2020 they just deleted the scanner off Etrade Pro.(because they felt like it).Trading on Nasdaq you can use a lot of the features your broker offers for free, Well not free, you pay for it with commission. Anyway hope you success with what ever you choose. Also take advantage of the trials they offer.
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