Can email design elements be A/B tested?

Yes, email design elements can and should be A/B tested, though they present unique challenges:

Testable elements include: Single column versus multi-column layouts. Image placement and size. Color schemes and button colors. Typography choices. Whitespace and content density. Visual hierarchy and scanning patterns.

Challenges of design testing:

Effects are often subtle, requiring larger samples to detect. Design interacts with content, making isolation difficult. Rendering varies across email clients, potentially confounding results.

Best practices: Test one visual element at a time. Use click maps and heat maps when available. Consider device-specific analysis since design impacts mobile and desktop differently.

Design tests answer "how people see" while content tests answer "what people read." Both matter, but design effects are typically smaller and harder to measure.