Email Design Cheat Sheet 2026

The 30 highest-yield Email Design facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What is a 'bulletproof button' in HTML email coding? → A CTA button built with HTML/CSS that renders correctly even when images are blocked
2. What HTML element is primarily used to create table-based email layouts? →
3. What is the maximum recommended total file size for an HTML email? → 102KB
4. What does 'conversion rate' measure in the context of email CTAs? → The percentage of subscribers who clicked the CTA and completed the desired action
5. What is the most effective way to use email signature marketing? → As part of your omni-channel marketing strategy
6. Which layout approach places the main content area next to a narrower sidebar? → Sidebar (two-column) layout
7. Which property controls the space between lines of text in email CSS? → line-height
8. What is the best way to make your email look more professional? → Use a two-column layout
9. What coding technique makes images in emails scale down properly on mobile? → Setting max-width: 100% and height: auto on the tag
10. What color model is used when specifying colors in HTML email code? → RGB/Hex
11. Which font type is considered safest to use in HTML emails for cross-client compatibility? → System/web-safe fonts
12. What is the recommended line length (in characters) for optimal email body text readability? → 50–75 characters
13. What is the CSS media query used to apply mobile-specific styles in responsive emails? → @media screen and (max-width: 600px)
14. What does using a 'call-to-action button color' that contrasts with the email background achieve? → Draws the subscriber's eye to the most important action
15. In email design, what is a 'hero' image? → A large, prominent image at the top of the email
16. What value should the border attribute be set to on email layout tables? → border='0'
17. Which CSS property sets the background color of an HTML email table cell? → background-color
18. What is the recommended minimum font size for body text in marketing emails? → 14px
19. What is the correct way to ensure a linked image in an email has no blue border? → Add border='0' to the tag and border: 0 inline CSS
20. What is 'white space' (negative space) in email design? → Empty areas around content elements that improve readability and visual balance
21. Which email section typically contains the logo, navigation links, and branding? → Header
22. Which type of CTA language typically performs best for lead generation emails? → Value-focused ('Download Your Free Guide')
23. What is 'scannability' in the context of CTA placement? → Designing email content so subscribers can quickly spot the CTA while skimming
24. What visual design technique makes a CTA button look clickable (affordance)? → Adding rounded corners, shadow effects, and contrasting colors to suggest interactivity
25. What is a 'font stack' in email CSS? → A prioritized list of fonts with fallbacks
26. Which CSS property is most commonly used to make images scale responsively in email layouts? → max-width: 100%
27. What does the cellpadding attribute control in an HTML email table? → The space between the cell border and its content
28. Why should email designers avoid using very light gray text on a white background? → It fails minimum contrast ratio requirements and is hard to read
29. Which attribute should always be included with email images for accessibility? → alt
30. What does the attribute on the tag help with in email accessibility? → It tells screen readers and translation tools what language the email is written in