How to Test an Email Before Sending: A Pre-Send Checklist

A broken link or an empty first name in front of your whole list is easy to prevent. Run through this checklist before every send.

Send a test to yourself

Send the test to real inboxes, ideally Gmail, Outlook and an Apple device. Open it on your phone as well as on a computer. Email apps render messages differently, so a single preview is not enough.

The checklist

• Subject line and preheader read well together and have no typos.
• Every link goes where it should. Click each one.
• Images load, have alt text, and the email still makes sense with images off.
• The layout works on a narrow phone screen, and buttons are easy to tap.
• Merge tags such as the first name fill in, and there is a sensible fallback when a name is missing.
• The unsubscribe link works and your postal address is present.
• Colors still read well in dark mode.
• The email has a plain-text version if your platform supports one.
• Total size is reasonable. Gmail clips very large messages, so keep your HTML lean.

Check accessibility

• Use enough contrast between text and background.
• Keep body text at a readable size, around 14 to 16 pixels.
• Use real headings and descriptive link text, not just "click here".

Send to a small group first

If your platform allows it, send to a small segment first and check the results before sending to everyone. For important sends, ask a colleague to review the test too.

Use our tools

Our HTML email best practices guide explains why emails behave differently across apps, and the newsletter builder previews desktop and mobile as you work.