Preview Text (or Pre-header text)

Preview text is the short snippet beside the subject line that previews the email and encourages opens.

Definition & Examples

What is Preview Text?

Preview text (also called pre-header text) is the short snippet of text that appears next to or below the subject line in an email inbox, offering a brief preview of the email's content. This secondary line of text provides recipients with additional context about the email before they decide whether to open it.

Most email clients automatically pull the first line of text from your email content as preview text. However, smart marketers intentionally craft this text to work alongside the subject line to maximize open rates.

Why it matters

• Increased open rates: Well-crafted preview text can boost open rates by 15-30%

• Better first impression: Provides additional context to your subject line

• Competitive advantage: Helps your email stand out in crowded inboxes

• Message clarity: Reduces ambiguity about your email's content

• Mobile optimization: Particularly important on mobile devices with limited screen space

How preview text works

Technical implementation

Preview text is typically implemented using hidden HTML in your email template:

<div style="display:none;font-size:1px;color:#ffffff;line-height:1px;max-height:0px;max-width:0px;opacity:0;overflow:hidden;">
Your preview text goes here
</div>

Email client behavior

Different email clients display preview text differently:

• Gmail: Shows 90-110 characters on desktop, 35-40 on mobile

• Apple Mail: Displays 35-140 characters depending on device

• Outlook: Shows 55-90 characters across versions

• Yahoo Mail: Displays approximately 150 characters

Automatic extraction

If you don't set custom preview text, email clients will automatically pull text from:

1. First line of email content

2. ALT text from images

3. Random HTML elements

4. Default messages like "View this email in your browser"

Preview text strategies

Complementary approach

Work with your subject line to tell a complete story:

• Subject: "Your exclusive 20% discount is here"

• Preview: "Save on bestsellers before midnight tonight"

Curiosity gap technique

Create intrigue that compels opens:

• Subject: "The mistake that cost us $10K"

• Preview: "And how it led to our biggest breakthrough"

Benefit amplification

Reinforce the value proposition:

• Subject: "New feature: Team collaboration"

• Preview: "3x faster project completion for growing teams"

Urgency reinforcement

Add time-sensitive elements:

• Subject: "Last chance: Early bird pricing"

• Preview: "Only 6 hours left to secure 40% off"

Social proof integration

Include credibility elements:

• Subject: "See what 10,000+ users are saying"

• Preview: "Real testimonials from your industry peers"

Best practices for preview text

Length optimization

Character limits by client:

• Mobile devices: 30-40 characters

• Desktop clients: 90-150 characters

• Optimal range: 40-90 characters for broad compatibility

Testing recommendations:

• Preview across multiple email clients

• Test on both mobile and desktop

• Use tools like Litmus or Email on Acid

• Check how preview text appears when truncated

Content guidelines

What to include:

• Key benefits or value propositions

• Compelling calls-to-action

• Personalization elements

• Time-sensitive information

• Social proof indicators

What to avoid:

• Repeating the exact subject line

• Generic phrases like "View in browser"

• Lorem ipsum or placeholder text

• Misleading or clickbait content

• All caps or excessive punctuation

Personalization opportunities

• Use subscriber names or company information

• Reference past purchases or behaviors

• Include location-specific details

• Mention subscriber preferences or interests

Advanced preview text techniques

A/B testing approaches

Subject line and preview text combinations:

• Test different preview text with the same subject line

• Test same preview text with different subject lines

• Test completely different combinations

Content variations:

• Benefit-focused vs feature-focused

• Question vs statement format

• Urgency vs value-focused messaging

• Personal vs professional tone

Mobile-first optimization

Mobile considerations:

• Shorter character counts for mobile displays

• Front-load important information

• Use active voice and strong verbs

• Avoid complex punctuation that might truncate poorly

Testing methodology:

• Preview on actual mobile devices

• Test across iOS and Android platforms

• Check various email apps (Gmail, Apple Mail, Outlook)

• Verify preview text isn't cut off mid-word

Dynamic preview text

Content automation:

• Use merge tags for personalization

• Pull in product names or details

• Include real-time information (dates, weather, stock levels)

• Reference recent subscriber activities

Segmentation-based preview text:

• Different messages for different subscriber segments

• Industry-specific language for B2B audiences

• Geographic customization for local relevance

• Behavioral triggers for targeted messaging

Common preview text mistakes

Default or missing preview text

Problem: Email clients pull random text from email body

Solutions:

• Always set intentional preview text

• Use hidden HTML div method for clean implementation

• Test preview text across multiple clients

• Regularly audit automated campaigns for preview text

Subject line repetition

Problem: Preview text exactly repeats subject line content

Solutions:

• Use preview text to expand on subject line promise

• Add complementary information or benefits

• Create curiosity gaps between subject and preview

• Provide additional context or urgency

Misleading preview content

Problem: Preview text doesn't match actual email content

Solutions:

• Ensure preview text accurately represents email content

• Avoid clickbait or misleading promises

• Maintain consistency between preview and email body

• Focus on genuine value propositions

Poor mobile optimization

Problem: Preview text gets cut off or doesn't display well on mobile

Solutions:

• Front-load most important information

• Keep critical content within first 35-40 characters

• Test across multiple mobile email clients

• Use concise, impactful language

Measuring preview text effectiveness

Key metrics to track

Open rate analysis:

• Compare open rates before and after preview text optimization

• Track performance across different email clients

• Monitor mobile vs desktop open rate differences

• Analyze segment-specific performance

A/B testing metrics:

• Statistical significance of preview text variations

• Engagement rate differences

• Click-through rate impact

• Conversion rate correlation

Performance optimization

Continuous improvement:

• Regular A/B testing of preview text variations

• Monitor industry benchmarks and best practices

• Analyze competitor preview text strategies

• Update preview text based on seasonal or campaign needs

Data-driven decisions:

• Use email analytics to identify top-performing preview text

• Correlate preview text performance with subject line data

• Track long-term trends in preview text effectiveness

• Document successful patterns for future campaigns

Preview text across email types

Newsletter campaigns

• Highlight featured content or articles

• Mention exclusive subscriber benefits

• Include publication frequency reminders

• Add social proof or subscriber counts

Promotional emails

• Emphasize discount amounts or savings

• Include time-sensitive urgency elements

• Mention product names or categories

• Add shipping or return policy benefits

Transactional emails

• Provide order or account status updates

• Include helpful next steps or actions

• Add customer service contact information

• Mention security or verification details

Welcome series

• Set expectations for future emails

• Highlight onboarding benefits or resources

• Include brand personality elements

• Provide quick value or tips

Industry-specific considerations

E-commerce and retail

• Include product names and prices

• Mention inventory levels or availability

• Add shipping deadlines for promotions

• Use seasonal or trending keywords

SaaS and technology

• Highlight feature names and benefits

• Include user statistics or growth metrics

• Mention integration or compatibility details

• Use technical terms appropriate for audience

B2B services

• Reference industry-specific pain points

• Include case study or ROI information

• Mention compliance or security benefits

• Use professional, authoritative language

Tools and resources for preview text

Email testing platforms

• Litmus: Comprehensive email client previews

• Email on Acid: Cross-client preview testing

• Loops preview: Built-in preview functionality

• Campaign Monitor: Email client testing tools

Preview text generators

• Online tools for character count optimization

• Subject line and preview text combination testers

• Mobile preview simulators

• A/B testing idea generators

Analytics and optimization

• Email platform analytics for preview text performance

• Heat mapping tools for inbox engagement

• A/B testing statistical significance calculators

• Conversion tracking and attribution tools

Future trends in preview text

Emerging technologies

• AI-powered preview text generation: Machine learning algorithms creating optimized preview text

• Dynamic real-time content: Preview text that updates based on current events or data

• Interactive preview elements: Rich previews with buttons or interactive components

• Voice assistant integration: Preview text optimized for voice email reading

Evolving best practices

• Accessibility improvements: Better preview text for screen readers and assistive technologies

• Privacy-focused optimization: Preview text strategies that work with increased email privacy measures

• Cross-channel coordination: Preview text that aligns with SMS, push notifications, and social media

• Behavioral prediction: Preview text optimized based on predicted subscriber actions

Related terms

• Subject line

• Email header

• Inbox placement

• Open rate

Key takeaways

• Preview text is a powerful but often overlooked tool for improving email open rates

• Always set intentional preview text rather than letting email clients pull random content

• Keep preview text concise (40-90 characters) while providing meaningful value

• Test preview text across multiple email clients and devices for optimal display

• Use preview text to complement and enhance your subject line, not repeat it