The SpamPatrol wordpress plugin provides support for Contact Form 7, Ninja Forms and Formidable Forms.
To install the plugin go to Plugins » Add New from your WP Admin Dashboard then search for "spampatrol" then click Install.
After installing the plugin you only need to Activate then it's ready for use. Supported form plugins will be automatically picked up.
The plugin settings can be found under Settings » SpamPatrol and will provide fields for configuring your API key, spam threshold and actions for when spam is detected.
To start using with Contact Form 7 the spampatrol:content attribute should be added to any text field that should be analyzed during submission.
To use with Ninja Forms Dev Mode must be enabled in order to view the field settings. To enable visit the Ninja Forms» Settings page and enable Dev Mode.
Once Dev Mode is enabled any text field that needs to be analyzed can be indicated by appending _spampatrol to the field key.
To use with Formidable Forms any text field that needs to be analyzed should have _spampatrolappended to the Field Key found under the Field Options » Advanced area.