npx skills add ...
npx skills add halt-catch-fire/superpowers --skill youtube-thumbnail-design
YouTube thumbnail design with specific dimensions, contrast rules, and mobile preview optimization. Covers safe zones, text placement, face expression psychology, and A/B testing. Use for: YouTube thumbnails, video cover images, click-through optimization. Triggers: youtube thumbnail, thumbnail design, video thumbnail, click through rate, ctr optimization, youtube cover, video cover image, thumbnail maker, thumbnail tips, youtube design, video preview image
npx skills add halt-catch-fire/superpowers --skill youtube-thumbnail-design
Install the belt CLI skill:
npx skills add belt-sh/cli
Create high-CTR YouTube thumbnails with AI image generation via inference.sh CLI.
Requires inference.sh CLI (
belt). Install instructions
| Spec | Value |
|---|---|
| Dimensions | 1280 x 720 px (minimum) |
| Recommended | 1920 x 1080 px |
| Aspect ratio | 16:9 |
| Max file size | 2 MB |
| Formats | JPG, GIF, PNG |
Your thumbnail appears at roughly 120px wide on mobile — that's how most viewers first see it.
At 120px, viewers must be able to identify:
Test: view your thumbnail at 120px width. If it's a muddy blur, redesign.
Avoid placing critical elements in:
| Combination | Mood | Best For |
|---|---|---|
| Yellow + Black | Urgency, attention | Tech, business, lists |
| Red + White | Energy, excitement | Entertainment, reactions |
| Blue + Orange | Professional contrast | Education, tutorials |
| Green + White | Growth, money | Finance, success stories |
| Purple + Yellow | Premium, creative | Design, art, creativity |
| White + Dark | Clean, minimal | Luxury, minimalist channels |
| Rule | Reason |
|---|---|
| Max 6 words | Readability at thumbnail size |
| Min 60pt equivalent | Must be legible at 120px width |
| Bold sans-serif font | Thin fonts disappear at small sizes |
| Contrast stroke/shadow | Ensures readability on any background |
| No small text | If it's not readable small, cut it |
Thumbnails with faces get higher CTR than faceless thumbnails. Expression matters:
| Expression | CTR Impact | Best For |
|---|---|---|
| Surprise/shock | Highest | Reaction, reveal, discovery content |
| Curiosity | High | Tutorial, how-to, tips |
| Excitement | High | Unboxing, reviews, announcements |
| Concern/worry | Medium-high | Warning, mistake, problem content |
| Confidence | Medium | Expert advice, authority content |
| Neutral | Lowest | Avoid unless your brand is minimalist |
Test one variable at a time:
| Variable | Test A vs B |
|---|---|
| Face vs No face | Same composition, with/without person |
| Expression | Surprise vs curiosity |
| Color scheme | Warm vs cool palette |
| Text vs No text | With/without text overlay |
| Background | Bright vs dark |
| Composition | Left-facing vs right-facing subject |
| Mistake | Problem | Fix |
|---|---|---|
| Too much text | Unreadable at thumbnail size | Max 6 words or no text |
| Low contrast | Disappears in the feed | Use complementary colors |
| Cluttered composition | Eye doesn't know where to look | One focal point |
| Generic stock photo feel | No personality, gets skipped | Authentic expressions, unique angles |
| Tiny details | Lost at 120px | Bold, simple shapes |
| Same style every video | Viewer fatigue | Vary within brand guidelines |
| Misleading thumbnail | Kills trust, hurts retention | Match the actual content |
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