This case study explores an A/B testing campaign conducted to evaluate how email tone, structure, and design affect audience engagement. The goal was to identify the combination of elements that resonate most effectively with readers and drive stronger interaction. Two distinct email versions were created and analyzed using both quantitative metrics and qualitative observations.

1. Objective
The objective was to determine how different writing tones and design styles influence engagement rates. Version A represented a formal, text-focused email designed for clarity and conciseness, while Version B used a conversational tone, structured visuals, and repositioned CTAs for greater user engagement.

2. Methodology & Process

The experiment followed a structured approach combining creativity with analytical testing. Both emails were designed in Canva and deployed via Mailchimp to ensure consistent delivery conditions. The process involved the following steps:
• 1. Defined a clear goal to enhance reader engagement and optimize message flow.
• 2. Developed two email versions (A & B) differing in tone, structure, and CTA placement.
• 3. Ensured equal audience segmentation to maintain unbiased performance comparison.
• 4. Scheduled both versions simultaneously to avoid timing bias.
• 5. Measured open rates, CTRs, read times, and unsubscribe rates through Mailchimp analytics.
• 6. Collected qualitative feedback on design clarity, tone, and readability.

3. Email Version Structure Comparison

Version Subject Line Tone & Design CTA Placement Goal
A (Control) Explore This Week’s Marketing Highlights Professional, text-heavy, single CTA at the end Bottom Deliver structured updates
B (Variation) Ready to Discover What’s Trending in Marketing? Conversational tone, visuals, mid-body CTA Middle Increase engagement and readability



4. Results & Insights

Quantitative results highlighted clear differences between both email versions. Version B consistently outperformed Version A across all engagement metrics, confirming that design flow and tone significantly affect user interaction.

Metric Version A Version B Change
Open Rate 18% 25% +7%
Click-Through Rate (CTR) 4.5% 6.2% +1.7%
Read Time (Avg.) 21 sec 29 sec +8 sec
unsubscribe Rate 1.1% 0.8% ↓ 0.3%


Version B’s conversational subject line and visually guided layout captured attention early and held it longer. Readers engaged more deeply with segmented content, shorter paragraphs, and interactive CTAs. The control version (A) remained effective for formal updates but lacked visual rhythm, resulting in faster drop-offs.

5. Strengths & Weaknesses

Aspect Version A (Control) Version B (Variation)
Tone Professional, clear, structured Friendly, conversational, approachable
Design Minimal layout with focus on text Visual-forward with icons and highlights
CTA Placement End of email Mid-body CTA to sustain interaction
Audience Fit Corporate and formal audiences Broader marketing and creative segments
Strengths Simplicity, clarity, easy to follow High engagement, visually appealing, interactive
Weaknesses Lower engagement, less visual stimulation Informal tone may not fit all audiences
6. Key Learnings

• Audience behavior responds strongly to tone and visual hierarchy.
• Early CTA placement improves engagement and reduces attention drop-off.
• Balance between professionalism and creativity drives sustained reader interest.
• Qualitative insights are essential to validate quantitative metrics.
• Personalization and storytelling enhance emotional connection and retention.

7. Conclusion & Future Application

This A/B testing initiative underscored the importance of uniting data analytics with creative design thinking. Version B’s success demonstrated that tone, layout, and visual strategy work synergistically to elevate engagement. Future campaigns will leverage these insights to build even more targeted, visually engaging, and user-centered email experiences.

Tools Use

• Mailchimp – Email distribution and analytics tracking
• Canva / Figma – Email layout design and visualization
• Power BI / Excel – Data analysis and visualization of performance metrics
• Hemingway & Grammarly – Tone and readability optimization
• Notion – Documentation and campaign tracking