Email Template Tester
Test HTML emails across different devices and email clients. Check deliverability and responsive design.
HTML Email Template
Click to upload or drag and drop
Upload HTML file
Maximum file size: 1 MB
Preview Settings
Preview
Tips:
- Use table-based layouts for better email client compatibility
- Avoid external CSS - use inline styles instead
- Test images with alt text for accessibility
- Keep file sizes under 100KB for better deliverability
About the Email Template Tester
The Email Template Tester lets you preview HTML emails across different devices and clients so you can check how your design renders before sending. Email rendering is notoriously inconsistent, and previewing catches problems early.
An email that looks perfect in one client can break in another — broken layouts, missing styles, or unreadable text on mobile. Testing your HTML beforehand helps you catch responsive issues and deliverability concerns so recipients see what you intended.
Testing happens in your browser, so your email content never leaves your device. There’s no upload or account; paste your HTML and preview it privately.
How to use the Email Template Tester
- Paste your email’s HTML into the tool.
- Preview how it renders.
- Check the layout across different device sizes.
- Note any rendering or responsiveness issues.
- Adjust your HTML and re-test until it looks right.
Common use cases
- Checking an email design before sending a campaign.
- Verifying that an email is readable on mobile.
- Catching broken layouts across email clients.
- Reviewing responsive behavior of an HTML email.
Frequently asked questions
Why do emails render differently across clients?
Email clients support different subsets of HTML and CSS, so the same code can look different in each. Previewing helps you spot where your design may break.
Can I check mobile rendering?
Yes. Previewing across device sizes helps you confirm your email is readable and well-laid-out on phones as well as desktops.
Does it test deliverability too?
It focuses on how your HTML renders. Deliverability also depends on factors like your sending setup and content, which are handled outside the design itself.
Is my email content uploaded?
No. Testing runs in your browser, so your content never leaves your device.
How do I create the HTML in the first place?
You can write it yourself or convert content with the Markdown to Email tool, then test it here.