diff --git a/index.php b/index.php
index a13fe0e..c38923f 100644
--- a/index.php
+++ b/index.php
@@ -306,7 +306,7 @@
                                 </div>
                             </div>
                             <div class="mb-3">
-                                <input type="email" class="form-control" name="email" placeholder="email@website.com" required>
+                                <input type="email" class="form-control" name="email" placeholder="email@website.com" autocomplete="email" inputmode="email" autocapitalize="off" spellcheck="false" maxlength="190" required>
                             </div>
                             <div class="mb-3">
                                 <input type="text" class="form-control" name="company" placeholder="Company">
@@ -352,9 +352,39 @@
             const formData = new FormData(form);
             const messageDiv = document.getElementById('form-message');
             const rightColumn = document.getElementById('right-column-content');
+            const emailInput = form.querySelector('input[name="email"]');
+            const emailValue = (emailInput.value || '').trim().toLowerCase();
+            const blockedDomains = new Set([
+                '10minutemail.com',
+                'dispostable.com',
+                'emailondeck.com',
+                'fakeinbox.com',
+                'guerrillamail.com',
+                'maildrop.cc',
+                'mailinator.com',
+                'mailnesia.com',
+                'mintemail.com',
+                'sharklasers.com',
+                'tempmail.com',
+                'temp-mail.org',
+                'trashmail.com',
+                'yopmail.com',
+                'example.com',
+                'example.net',
+                'example.org'
+            ]);
 
             messageDiv.textContent = ''; // Clear previous messages
 
+            if (emailValue && emailValue.includes('@')) {
+                const emailDomain = emailValue.split('@').pop();
+                if (blockedDomains.has(emailDomain)) {
+                    messageDiv.textContent = 'Please use your real email address. Temporary or disposable inboxes are not allowed.';
+                    emailInput.focus();
+                    return;
+                }
+            }
+
             fetch('register.php', {
                 method: 'POST',
                 body: formData
diff --git a/register.php b/register.php
index afbbe54..fe380f9 100644
--- a/register.php
+++ b/register.php
@@ -5,6 +5,75 @@ require_once 'mail/MailService.php';
 
 header('Content-Type: application/json');
 
+function normalize_email_address($email) {
+    return strtolower(trim((string) $email));
+}
+
+function has_valid_email_dns($domain) {
+    if ($domain === '') {
+        return false;
+    }
+
+    return checkdnsrr($domain, 'MX') || checkdnsrr($domain, 'A') || checkdnsrr($domain, 'AAAA');
+}
+
+function is_disposable_email_domain($domain) {
+    static $blocked_domains = [
+        '10minutemail.com',
+        'dispostable.com',
+        'emailondeck.com',
+        'fakeinbox.com',
+        'guerrillamail.com',
+        'maildrop.cc',
+        'mailinator.com',
+        'mailnesia.com',
+        'mintemail.com',
+        'sharklasers.com',
+        'tempmail.com',
+        'temp-mail.org',
+        'trashmail.com',
+        'yopmail.com',
+        'example.com',
+        'example.net',
+        'example.org',
+    ];
+
+    return in_array($domain, $blocked_domains, true);
+}
+
+function validate_registration_email($email) {
+    $email = normalize_email_address($email);
+
+    if ($email === '' || !filter_var($email, FILTER_VALIDATE_EMAIL)) {
+        return 'Please enter a valid email address.';
+    }
+
+    if (strlen($email) > 190) {
+        return 'Please enter a shorter email address.';
+    }
+
+    $parts = explode('@', $email);
+    if (count($parts) !== 2) {
+        return 'Please enter a valid email address.';
+    }
+
+    [$local, $domain] = $parts;
+
+    if ($local === '' || $domain === '') {
+        return 'Please enter a valid email address.';
+    }
+
+    if (is_disposable_email_domain($domain)) {
+        return 'Please use your real email address. Temporary or disposable inboxes are not allowed.';
+    }
+
+    if (!has_valid_email_dns($domain)) {
+        return 'Please use an email with a real mail domain.';
+    }
+
+    return null;
+}
+
 // --- Helper function to fetch webinar details ---
 function get_webinar_details($id) {
     if (empty($id)) return null;
@@ -34,7 +103,9 @@ if (!$webinar) {
 }
 
 // --- DATA CAPTURE ---
-$email = filter_input(INPUT_POST, 'email', FILTER_VALIDATE_EMAIL);
+$email_input = (string) filter_input(INPUT_POST, 'email', FILTER_UNSAFE_RAW);
+$email = normalize_email_address($email_input);
+$email_error = validate_registration_email($email);
 $first_name = filter_input(INPUT_POST, 'first_name', FILTER_SANITIZE_STRING);
 $last_name = filter_input(INPUT_POST, 'last_name', FILTER_SANITIZE_STRING);
 $company = filter_input(INPUT_POST, 'company', FILTER_SANITIZE_STRING);
@@ -53,11 +124,16 @@ $allowed_sources = [
 ];
 
 // --- VALIDATION ---
-if (!$first_name || !$last_name || !$email || $how_did_you_hear === '') {
+if (!$first_name || !$last_name || $email === '' || $how_did_you_hear === '') {
     echo json_encode(['success' => false, 'error' => 'Please fill out all required fields.']);
     exit;
 }
 
+if ($email_error !== null) {
+    echo json_encode(['success' => false, 'error' => $email_error]);
+    exit;
+}
+
 if (!in_array($how_did_you_hear, $allowed_sources, true)) {
     echo json_encode(['success' => false, 'error' => 'Please choose how you heard about this webinar from the list.']);
     exit;