how to avoid bot attacks on form

Question

i have these forms:

https://www.mychabad.org/templates/articlecco.asp?aid=1188756&jewish=General-Contributions.htm&lang=en&site=chabaduc.org

https://www.mychabad.org/templates/articlecco.asp?AID=1189379

https://www.mychabad.org/templates/articlecco.asp?aid=1189287&jewish=Shabbat-Holiday-Sponsorships.htm&lang=en&site=chabaduc.org

and last night they were attacked by a bunch of submissions

1. is there anything simple i can with the code to avoid such attacks?
2. if not, should i be using a different form service?

Answer 1

Try putting an empty field in the page, hide it via CSS and check if it's filled in. (Perhaps with a note beside that says to leave it empty in case a user has CSS disabled.) Many bots will fill every field in, so you can check if this field is empty.