1. ---

   '); // Add dark mode styles if needed if ($color_scheme === 'dark') { $dark_mode_css = ' '; // Check if there's a head tag if (strpos($html, '') !== false) { $html = str_replace('', $dark_mode_css . '', $html); } else { // If no head tag, add it $html = '' . $dark_mode_css . '' . $html; } } // Process version B for A/B testing if ($testing_mode === 'ab' && !empty($html_b)) { $html_b = strip_tags($html_b, '

   Welcome!

   This is a basic email template that works across different email clients.

   `, newsletter: `

   Newsletter

   Column 1

   Your content here...

   Column 2

   Your content here...

   Footer content here

   `, promotional: `

   Special Offer!

   Limited time promotion

   Don't Miss Out!

   Your promotional content here...

   Shop Now

   `, welcome: ` `, confirmation: ` `, abandoned_cart: ` `, event_invitation: ` `, feedback_request: ` ` }; // Template Selection document.querySelectorAll('[data-template]').forEach(button => { button.addEventListener('click', function() { const template = this.dataset.template; const targetInput = document.querySelector('[name="testing_mode"]:checked').value === 'ab' && document.activeElement.closest('#versionB') ? 'html_b' : 'html'; document.getElementById(targetInput).value = templates[template]; bootstrap.Modal.getInstance(document.getElementById('templateModal')).hide(); }); });

   How to Use This Tool

   1. Enter your data in the form above.
   2. Click the action button to run the check.
   3. Review the results table or output area.
   4. Download or copy results if needed.
   5. Use related tools for deeper validation.

   What This Result Means

   Green or positive indicators mean the check passed. Warnings highlight addresses or settings that may cause bounces or spam folder placement. Red or failed checks should be fixed or removed before sending email. Use the breakdown to decide whether to keep, quarantine, or delete each address.

   Frequently Asked Questions

   Is the HTML Email Preview free?

   Yes. This tool is free to use with no account required for basic checks.

   Do you store my data?

   We process input to deliver results and do not sell your data. Avoid pasting sensitive information when possible.

   How accurate are the results?

   Results use standard DNS and format checks. For mission-critical lists, combine multiple tools and periodic re-checks.

   Can I use this for bulk lists?

   Yes for supported tools. For large CSV files use our bulk CSV verifier or list cleaner.

   Related Tools

   HTML Analyzer

   Compatibility check

   Signature Generator

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   Mailto Generator

   Mailto links

   Example Use Cases

   Pre-campaign list hygiene

   Run the HTML Email Preview before sending newsletters to reduce bounces and protect sender reputation.

   Sign-up form quality

   Developers and marketers use this at registration to block bad addresses early.

   Sales prospect research

   Sales teams validate contact data before outreach to improve connect rates.