php-antispam

The Invisible protection from spam, no captcha, no recaptcha, no puzzles, no math captcha.

API for antispam service cleantalk.org

Requirements

• PHP 5.6 and above
• CURL support

How we stop spam?

PHP Anti-Spam library providing invisible spam protection for your websites, registration forms, and comment sections. CleanTalk API offers an effective CAPTCHA alternative that silently blocks spam without interrupting your users' experience.

When users submit forms on your website form, the form data is securely sent to CleanTalk’s cloud servers. CleanTalk analyzes submissions using advanced heuristics. CleanTalk then returns a real-time verdict— legitimate requests or spam.

You are free to do anything with spam, or just allow as to block spam (we will interrupt desirable request).

CleanTalk vs CAPTCHA

Feature	CleanTalk Anti-Spam	Traditional CAPTCHA
User Interaction	100% invisible to users	Requires solving puzzles or clicks
Form Compatibility	Works with any PHP form	Often requires additional scripts
Speed	Instant cloud check	Slower due to user interaction
Accessibility	Fully accessible, no visual tests	Often inaccessible to screen readers

CleanTalk is a PHP spam filter and a captcha-free alternative that boosts UX and protects your forms with zero friction.

Interesting? Let's make some settings (it will take few minutes)

Step 1 - install our SDK (2 variants ability)

Through composer install OR through download zip arhive and unzip it to root directory (with your index.php)

composer require cleantalk/php-antispam

Step 2 - add CleantalkAntispam handler (middleware/interception) to your form handler (action)

$apikey = ''; // get it here cleantalk.org (free trial)
$email_field = $_POST['email']; // get it from your form
$cleantalk_antispam = new CleantalkAntispam($apikey, $email_field);
$api_result = $cleantalk_antispam->handle();

Step 2.1 - add js lib to your html template

<script src="https://moderate.cleantalk.org/ct-bot-detector-wrapper.js"></script>

Need for gathering frontend data.

Step 3 - do whatever you want with cloud result

For example add die block for spam.

if ($api_result && $api_result->allow === 0) {
    die('Blocked. Spam protection OK. Reason: ' . $api_result->comment);
    // or make your own actions/logs/messages ...
}

Step 4 (not required) - we prepare for you special troubleshooting method

To find possible problems, just add follow snippet after getVerdict method.

// TROUBLESHOOTING: logging the suggestions
error_log($cleantalk_antispam->whatsWrong(true));

In example file you can see context.

Step 5 (not required) - if you have any question, please, feel free to ask it in issue here or in our tiket system

Examples

• api response description
• example with form handler

Don't want to deal with all this?

Universal solution for any CMS or custom website: https://github.com/CleanTalk/php-uni