Email Template Tester
Preview email HTML across devices and check client compatibility.
Compatibility report
No issues- Paste your email HTML to analyse it.
This previews your email at different widths and runs an automated code-compatibility check. It is not a pixel-accurate render in real Outlook/Gmail engines — that needs a screenshot service (e.g. Litmus). Use this to catch the code issues that break across clients before you send.
Frequently asked questions
Is this like Litmus?
It covers the code side: live device previews plus an automated compatibility check for CSS and markup that breaks in Outlook, Gmail and other clients. It does not take pixel-accurate screenshots inside each real client, which requires a paid rendering service.
Is my email uploaded anywhere?
No. Everything runs in your browser — your HTML never leaves your device.
What issues does it detect?
Flexbox/grid, absolute positioning, external stylesheets, scripts, CSS background images, web fonts, missing alt text, Gmail's 102 KB clipping limit and more, with a fix suggestion for each.