Free HTML Email Checker

Test and validate your HTML email templates. Preview layouts with Gmail-style sanitization, all in your browser.

Email HTML

HTML is sanitized in your browser to match common Gmail rules. Unsupported tags and styles are stripped before preview.

Gmail Preview
Compatibility Notes
CountLevelMessageRule
Paste HTML to see compatibility notes.

Gmail may ignore unsupported CSS even if it renders in other email clients.

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Overview

Why Use an HTML Email Checker?

Email clients strip unsupported markup and CSS. This free email template checker previews how Gmail sanitizes your HTML code so you can catch layout breaks before you send.

Email clients each have their own HTML sanitizer and CSS support matrix. Testing your email templates with Gmail-style rules helps you spot code that gets removed, styles that are ignored, and layouts that collapse in real inboxes.

Email Template Validation

Check your HTML email templates against Gmail-style sanitization rules. See exactly which tags and attributes are stripped.

HTML Code Checker

Validate your email HTML code for common issues. Test table structures, inline styles, and formatting before sending.

Common issues this email tester catches

  • Unsupported tags like scripts, forms, and media embeds.
  • CSS properties that Gmail ignores or rewrites.
  • Broken table layouts and spacing when `gap` is removed.
  • Custom fonts that fall back to system defaults.
Resources

Email Layout Resources

Keep your email notifications consistent with these guides and compatibility references.

MagicBell

Email Notifications API

Send transactional email notifications across providers with a single API.

Blog

Transactional Email Templates

Patterns and layouts you can use as a starting point.

External

Email Client Support Matrix

Reference which HTML and CSS features each email client supports.