Spammers regularly target WordPress contact form and recently this has become a huge problem. Luckily, there are ways to combat spammers using Akismet in combination with the great plugin Contact form 7.
 
Wordpress comes with Akismet pre-installed, so all you have to do is to setup your free account and get the API key to activate Akismet.
 
Once you have activated your account, all you have to do is to add the following lines to your contact form 7: For example
 
For the name field

[text* your-name akismet:author]

 
to your email field

[email* your-email akismet:author_email]

 
in the contact form.
 
Remember that using both the “akismet:author” and the “akismet:author_email” will give you the best chance to minimize spam on your contact forms.
 
Once these lines have been added akismet will filter the names and email addresses so only legit contacts will get through to you and it will cancel the sending of any spam related emails.