See exactly how your sender name, subject line, and preheader text will look in Gmail, mobile, and Apple Mail before you hit send.
Your weekly email performance report is...
Open rates are up 12% this week. See the full breakdown inside.
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Open rates are up 12% this week. See the full breakdown inside.
Your preheader should add new information, not echo the subject line. If the subject says "Your order shipped," the preheader could say "Arriving Thursday with tracking details inside."
Too short and email clients will fill the space with your HTML code or body text. Too long and it'll get cut off. Aim for 40-130 characters for the best coverage across devices.
Mobile clients show fewer characters. Put the most compelling or relevant information at the beginning so it's visible even when truncated.
The preheader is your second chance to get someone to open. Use it to tease the content, mention a deadline, or hint at something valuable inside the email.
Add your preheader text as the first element in your email HTML, then hide it visually with CSS. This gives you full control over what appears in the inbox preview.
What looks good on desktop might get cut off on mobile. Always preview across multiple clients before sending. That's exactly why this tool exists.
Preheader text (also called preview text or snippet text) is the short summary that appears next to or below the subject line in most email clients. It's the gray text you see in your inbox before you open a message. Think of it as a subtitle for your subject line.
Most email clients pull preheader text from the first visible text in the email body. If you don't set it explicitly, the recipient might see something like "View this email in your browser" or random navigation links — not exactly compelling stuff.
Your subject line gets people's attention, but the preheader closes the deal. Research shows that preheader text can boost open rates by 5-30%, depending on how well it's written. In a crowded inbox, that extra line of context can be the difference between an open and a skip.
On mobile devices, the preheader is even more important. Mobile email clients often show more preheader text than subject line text, which means your preview text might be the largest piece of copy visible before someone decides to open or swipe away.
Most email clients will pull text from the beginning of your email body. This often results in unhelpful text like "View in browser," your logo alt text, or random navigation links being shown. Always set an explicit preheader to control what your recipients see.
Most email marketing platforms have a dedicated preheader field in the editor. If you're coding HTML emails manually, add a hidden div or span at the very top of your email body with your preheader text, styled with display:none or using a zero-width approach.
Nearly all modern email clients show some form of preview text, including Gmail, Apple Mail, Outlook (desktop and mobile), Yahoo Mail, and Samsung Email. The length and display style varies — which is why it's important to preview across multiple clients.
This tool shows an approximation based on known character limits and display patterns. Actual rendering can vary slightly based on character width (narrow letters like 'i' take less space than 'M'), the user's font size settings, and screen resolution. It's close enough for planning purposes.
MailNeo gives you subject line testing, preheader optimization, and real-time deliverability monitoring in one platform.
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