Email Responsive Preview

Over 60% of emails are now opened on mobile devices, but most email developers build and test primarily on desktop. This responsive preview tool lets you see exactly how your email HTML renders at different viewport widths, from the smallest mobile phone (320px) to the standard email width (600px) to tablet landscape (768px). Catch layout issues before your subscribers do.

Why responsive testing matters for email

Email clients handle responsive design differently from web browsers. Not all email clients support media queries, and some have unique rendering quirks. Outlook uses the Word rendering engine which ignores most CSS. Gmail strips some media queries but supports inline styles. By previewing your email at different widths, you can see if your fallback styles work when media queries are ignored.

What to look for

Check that text remains readable at all widths without horizontal scrolling. Make sure buttons are large enough to tap on mobile (at least 44px tall). Verify that multi-column layouts stack properly on narrow screens. Check that images scale down without breaking the layout. Ensure your email footer remains readable and the unsubscribe link is easy to find on mobile.

Pair with other testing tools

After checking responsive behavior, run your HTML through the CSS inliner if you are using embedded styles. Check the email word counter since images and inline styles add up quickly. Use the accessibility checker to verify your email is usable for all subscribers. Finally, test your subject line length across the same devices to ensure the full experience is optimized.

For the best deliverability, make sure your email authentication is configured correctly. Check your SPF, DKIM, and DMARC records before sending to large lists.