How to protect yourself from spam on a landing page without losing conversion?

Question

PHP

I make landing pages on html, spam went on some sites. The fields are filled with some left data every time and a lot of messages.
It is necessary to solve the problem specifically for HTML landings, so that the script is lightweight and easy to set up.. without any dependencies, sessions, cookies, various captchas that spoil the conversion, etc....

Wrote a script for sending mail and banning by ip if the sending limit is exceeded per day https://github.com/Drilled-prog/Sender , I would like to know if it turned out okay and will it be effective in this case?

Answer 1

If they want to spam you, no captcha will help. The Indians solve it in manual mode for 3 kopecks.

Answer 2

Google captcha v3.

Answer 3

I can give you an idea how to do it without sessions and cookies. But it is important for me to know, do you yourself understand how the protection of sending data from bots takes place? Captcha technology - it has already been tested for years and there are simply no normal alternatives to it, and what I can offer you is a perversion. The question of protection against spam is the question of the quality of captcha execution. And any high-quality captcha is sessions and cookies. Here we are talking about the possibility of the first submission of your form, and not about processing several. If the first one is normal - okay. If not, then an error. Any other algorithm is flawed by definition.