Hello, I'd like to ask for suggestions please on a simple alternative to captcha. I've been getting a lot of spam through a contact form, meaningless stuff strings of letters / numbers.

I'm using Web form builder version 2.5. So it doesn't support any captcha that works anymore. (it worked with captcha 1 which stopped in 2018).

The form has a dropdown menu and another has radio buttons. This used to be enough to stop spam bots because they couldn't fill them out but it hasn't worked. I don't know whether it actually is a bot or a human doing it.

So my question is what else can I use?
Could I put a text field in and hide it? How would I get this to prevent the form submitting? like a honey pot for a bot to fill out but which a human couldn't see. I'm guessing simply hiding the submit button if this hidden field was filled out wouldn't work for a bot?

A simple what is 2+2? Type question, which obviously wouldn't stop human spammers?

Any suggestions please
Many thanks

I have often used some kind of maths, but spelling the numbers, also for the answer, and a tad more complicated than just 'two plus two'. But, because I often make sites in other languages than English, a lot of human spammers will be excluded by the language

You may also find alternatives if you google CAPTCHA, e.g. there are some with images and you are asked to select the ones showing something specific.

I've had success with regex. You'll never stop determined humans.
Use this to match 6
What's 3 + 3?

as always.... thank you Eric i have used your regex
Thank you Inger also. I will see if it helps things

I have the same issue. Regex works well if you can come up with a question that only people filling out the forms are going to be able to answer with a one word response. In my case it's RV related, and anyone filling out the form will have an RV. So my question is "color" of the tank that holds the yuckiest stuff on your rig" If you own an RV, you will know the answer is "black". Googling the question is not going give the answer, so a Russian whore trying to get you to click on sexy naked pictures of herself (I got those a lot) is unlikely to find the answer easily. So to take care of "black" and "BLACK" and "Black", I use this, you can just substitute your own words

/\bblack|BLACK|Black\b/

If you do it via Eric's method above which only involves a single character answer

/\b[black|BLACK|Black]\b/ I believe it will match any of the letters in black, so you don't want to do that.