Email Preview Text Generator

Preview text is the snippet that appears right after (or below) your subject line in the inbox. It's effectively a second subject line — and most marketers waste it. When you don't set preview text explicitly, email clients pull in whatever text comes first in your email body, which is usually "View in browser" or a navigation menu. That's prime inbox real estate showing throwaway content. This tool lets you craft your preview text with real-time previews across 8 major email clients, see exactly where it'll get truncated, and generate the HTML code with built-in invisible padding.

Character limits by email client

Every client shows a different amount of preview text, and it changes based on the device, subject line length, and screen width. Here are the approximate maximums: Gmail shows about 90 characters on desktop and 40-90 on mobile depending on subject line length. Apple Mail (iPhone) displays roughly 90 characters. Outlook desktop shows only about 35-50 characters. Yahoo Mail gives you around 100 characters. Write your most important message in the first 40 characters to cover every client, then use characters 40-90 to add supporting detail for clients that show more.

The hidden padding technique

Here's a problem: if your preview text is shorter than what the email client wants to display, it'll pull in visible content from the email body to fill the space. The fix is the hidden padding technique — after your preview text, you add a long string of invisible characters (alternating zero-width spaces and non-breaking spaces) wrapped in a hidden div. This "fills up" the preview text space with invisible content, preventing the client from showing your email's header links or other body text. This tool generates the HTML snippet automatically with roughly 150 characters of padding.

Writing preview text that drives opens

Think of your subject line and preview text as a one-two punch. The subject line hooks attention; the preview text closes the deal. Don't repeat the subject line — that wastes space and looks like a mistake. Instead, add context ("Here's what changed"), create urgency ("Offer expires tonight"), or tease value ("Including the template we use internally"). Questions work well too. If your subject line is "Your March metrics are in," your preview text could be "Open rates are up 12% — here's what drove it."

Integrating preview text into your workflow

Write your preview text at the same time as your subject line, not as an afterthought. Test both together with our subject line tester to evaluate the combined impact. Use our preheader generator for quick inspiration if you're stuck. And always check how your preview text renders alongside spam-checked content — our spam word checker catches trigger words that might flag the entire preview in spam filters. Finally, check the subject line length to make sure the subject doesn't eat into your preview text space on mobile.