Concise Studio

<h4>Algorithm</h4>
<ol>
<li>Plugin generates token on the backend side.</li>
<li>Plugin adds hidden field for token in each form which will use method “POST” after rendering of the page.</li>
<li>Plugin inserts token in the field after user’s interaction with site.</li>
</ol>
<h4>For developers</h4>
Antispam will automatically check submissions of the regular forms but ignores all AJAX requests. 
If you want to change this behaviour, you can use filter <code>concise_antispam_need_to_validate_token</code>. 
See example:
Disable Antispam for some forms:
<pre><code>add_filter("concise_antispam_need_to_validate_token", function($needToValidateToken) {
 if (!empty($_POST['do-not-check-antispam-token'])) {
 $needToValidateToken = false;
 }

 return $needToValidateToken;
});
</code></pre>
You can also always manually call <code>\Concise\Antispam::validateTokenOrDie()</code> in your custom handler.
<h3>Formidable Forms integration</h3>
For proper work disable the honeypot checking in the forms

Concise Antispam

Very simple antispam plugin. Users do not need to enter any captcha, working completely on background. No need to administer: just install the plugin  …

shawfactor

Why should your users prove that they’re humans by filling out captchas? Let bots prove they’re not bots with the <a href="http://lhero.org/plugins/lh-zero-spam/" rel="nofollow ugc">LH Zero Spam plugin</a>.
LH Zero Spam blocks registration spam and spam in comments automatically without any config or setup. Zero Spam was initially built based on the work by <a href="http://davidwalsh.name/wordpress-comment-spam" rel="nofollow ugc">David Walsh</a>, but enhanced with simpler code base and unobtrusive JavaScript.
Major features in LH Zero Spam include:
<ul>
<li>No captcha, because spam is not users’ problem</li>
<li>No moderation queues, because spam is not administrators’ problem</li>
<li>Blocks spam registrations & comments with the use of JavaScript</li>
<li>Blocks buddypress spam registrations with the use of JavaScript</li>
<li>Blocks woocommerce spam orders with the use of JavaScript</li>
</ul>
Like this plugin? Please consider <a href="https://wordpress.org/support/view/plugin-reviews/lh-zero-spam/" rel="ugc">leaving a 5-star review</a>.
Love this plugin or want to help the LocalHero Project? Please consider <a href="https://lhero.org/portfolio/lh-zero-spam/" rel="nofollow ugc">making a donation</a>.

LH Zero Spam

The plugin itself works perfectly and if you like lightweight unobtrusive solutions it is the way to go



Ben Marshalls commenty is unhelpful

Zero Spam makes blocking spam comments and registrations easy.

Concise Antispam vs LH Zero Spam