The best alternatives to I am not a Robot are Market Test, Humans Not Invited, and Squat Captcha. If these 3 options don't work for you, we've listed a few more alternatives below.
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Hurree— The smarter, simpler way to analyze your data
Do you trust your AI-generated content? Market Test is a fast way to test both human creative and AI-generated content on 100 real consumers. Perform iterative and agile testing in minutes, with results within two hours.
Humans Not Invited is a CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) that filters out humans and only lets programs pass. This is the first iteration of a system that we’re working on.
This captcha forces you to do 10 squats to continue. Works with chrome/firefox, desktop environment and also a webcam is required. There is available a Chrome extension to prevent compulsive purchases on amazon, more info https://bit.ly/3jS73YX