Many websites nowadays use Google’s reCAPTCHA service to try to verify that visitors are real people. While this is useful for preventing misuse of websites by bots, it also helps Google violate people’s privacy.
Also, because of their deliberately inaccessible nature, reCAPTCHA and other captchas cause serious accessibility problems for those with poor eyesight or hearing. The visual challenge is invisible to people using non-visual web browsers (such as screen readers), and the audio challenge can be very hard to make out.
If you run a website and value your site’s privacy and accessibility, you might want to consider alternatives to reCAPTCHA.
Do you really need reCAPTCHA?
There’s a very good essay thoroughly exploring the topic of Google reCAPTCHA, captchas in general and whether your site needs them.
It’s highly recommended that website maintainers give it a read before deciding which option is right for them.
Instead of asking humans to verify themselves, you can try tricking bots into revealing themselves by interacting with “honeypots”.
Honeypots are web page elements that are invisible to real humans, but visible to bots. If interaction is recorded with them, this may be enough to detect and counteract bots.
There are many websites with more details about this method.
Google did not invent the captcha, and there are others available which are more privacy-friendly.
The ones listed here are all libre and can be self-hosted.