Contact form spam protection

I have a simple contact form on my website which seems to be getting more and more spam entries. I have simple form validation but I would like to add some kind of anti spam bot mechanism to avoid the majority of spam coming in.

I have seen a plugin for wordpress I quite like ([url removed, login to view]) and I have seem other sites which ask people to fill in a simple maths problem i.e. 10 + 7.

I am happy for this to be a standard maths question (not dynamically generated) and for my PHP to validate if its the right answer before posting the message. If possible, I'd like the message to be retained so if a user makes a simple typo it doesn't get rid of their message so they can type the correct answer after one try or something

Ingenieurwesen JavaScript MySQL PHP Projektmanagement Softwarearchitektur Testen von Software Web Hosting Website-Management Testen von Webseiten

Projekt-ID: #3918101

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