Thumbnail Design System

The Split (for comparisons)

[OPTION A — left 50%] | [OPTION B — right 50%]
[     VS or arrow in center     ]

The Reveal (for tutorials/results)

[    RESULT / OUTCOME (large, center)    ]
[  Small "before" image + title text     ]

The Number

[   LARGE NUMBER (50% of thumbnail)    ]
[   Short text + face in corner        ]

3. Text Overlay Rules

• Max 3–5 words of text per thumbnail (more = unreadable at small size)
• Font size: text must be readable at 120×68px (YouTube mobile small)
• High contrast: white text + dark stroke, OR dark text + light background
• Bold weight: use font-weight 700–900 minimum
• Avoid: same font as the title card (differentiate thumbnail from title)

GOOD text overlays:
✅ "I Was WRONG"
✅ "$10k in 30 Days"
✅ "DO THIS NOW"
✅ "The SECRET Method"

BAD text overlays:
❌ "In this video I explain how to make money online using affiliate marketing"
❌ (no text — loses viewers who watch muted or on small screens)

4. Color Psychology

Rule: Use maximum 3 colors per thumbnail. One dominant, one secondary, one accent.

5. Technical Specs

Safe zone: Keep all key elements within center 80% — edges may be cropped on mobile.

6. A/B Testing

YouTube allows A/B thumbnail testing (YouTube Studio → Content → Test & Compare).

Test structure:

1. Create 2–3 thumbnail variants (change ONE element per variant)
2. Run for minimum 2,000 impressions per variant
3. Compare CTR (not just views)
4. Keep the winner; archive the losers

What to test:

• Face vs no face
• Text on left vs right
• Warm vs cool color palette
• Different facial expression (shocked vs confident vs happy)
• With vs without arrow/element pointing at subject

7. Checklist Before Publishing

• Readable at thumbnail size (128×72px preview)
• Strong contrast between subject and background
• Max 5 words of text
• Single focal point (not two competing subjects)
• Matches video title promise (no misleading thumbnail)
• Face shows clear emotion if included
• No competitor brand logos or copyrighted images
• File under 2MB