Email Dev Tools – Lessons in Email

Tools

Generate the right MSO conditional comments for targeting specific versions of Outlook — without wrestling with the syntax yourself.

Check text and background colour combinations against WCAG AA and AAA accessibility standards with a live preview.

Adjust opacity, contrast and saturation to optimise background images so they look great in both light and dark mode email clients.

Compare up to five typefaces side-by-side on a shared baseline to see how their x-heights and proportions stack up against each other.

Quickly verify whether a URL is configured with Access-Control-Allow-Origin: * so you can safely load external resources in email.

A browser extension (Chrome & Firefox) that lets you toggle CSS off on any page — handy for checking the HTML hierarchy of your email in the browser.

Free placeholder images built specifically for email — sized, formatted and ready to drop straight into your HTML.

Free HTML email testing tool. Paste your code and send a test in minutes.