Image Generation / Midjourney
Recommend –ar based on output use case — matches format to purpose, not habit.
Why This Prompt Exists
Most Midjourney users never change aspect ratio from the default 1:1. This forces square crops on content that should be wide or tall — losing composition, cropping subjects, and wasting resolution.
You get:
- Instagram posts cropped awkwardly (wrong ratio, heads cut off)
- YouTube thumbnails that don’t fit 16:9 (black bars or cropping)
- presentation slides with incorrect proportions (distorted images)
- print materials that don’t match standard paper sizes
- character portraits that should be vertical but come out square
But aspect ratios serve specific purposes:
- 1:1 — Instagram feed, profile pictures, icons, album art
- 4:3 — presentations, older displays, print photos
- 16:9 — YouTube, TV, monitors, widescreen presentations
- 9:16 — TikTok, Instagram Stories, Reels, vertical video
- 2:3 — standard portrait photography, print
- 3:2 — standard landscape photography, print
Without optimization, you crop later and lose quality.
This prompt recommends optimal aspect ratios by use case.
The Prompt
Assume the role of a Midjourney format consultant who recommends aspect ratios.
Your task is to recommend --ar values based on output use case.
Generate:
1. USE CASE CLASSIFICATION
- Output type: [SOCIAL / PRINT / PRESENTATION / WEB / VIDEO]
- Specific platform (if applicable): [e.g., Instagram, YouTube, TikTok]
- Orientation: [SQUARE / LANDSCAPE / PORTRAIT]
2. ASPECT RATIO RECOMMENDATION TABLE
| Use Case | Recommended --ar | Rationale | Alternative |
|----------|-----------------|-----------|-------------|
| Instagram feed post | 1:1 | Native square format | 4:5 for portrait |
| Instagram Story | 9:16 | Full-screen vertical | — |
| YouTube thumbnail | 16:9 | Standard video aspect ratio | — |
| TikTok video | 9:16 | Full-screen vertical | — |
| LinkedIn post | 1:1 or 16:9 | Square or widescale | 4:5 for carousel |
| Presentation slide | 16:9 or 4:3 | Monitor-standard | Depends on projector |
| Print - 8x10 photo | 4:5 | Matches print ratio | 5:4 for 10x8 |
| Print - wallet | 2:3 | Standard wallet size | — |
| Website hero image | 16:9 or 21:9 | Widescreen for banners | Depends on design |
| Character concept | 2:3 or 9:16 | Portrait orientation | 3:4 for closer crop |
3. PLATFORM-SPECIFIC DETAILS
**Instagram**
- Feed post (square): 1:1
- Feed post (portrait): 4:5 (1080x1350)
- Feed post (landscape): 1.91:1 (1080x608)
- Stories: 9:16 (1080x1920)
**YouTube**
- Thumbnail: 16:9 (1280x720 minimum)
- Channel banner: 16:9 with safe zone for mobile
**TikTok**
- All content: 9:16 (1080x1920)
**Print**
- 4x6 photo: 2:3
- 5x7 photo: 5:7
- 8x10 photo: 4:5
- A4 paper: 1:√2 (≈1:1.414)
4. COMPOSITION ADJUSTMENTS BY RATIO
- 1:1: Center subject, symmetrical compositions work well
- 16:9: Wide landscapes, group shots, cinematic framing
- 9:16: Vertical subjects, full-body portraits, tall buildings
- 4:5: Classic portrait crop (head and shoulders)
5. RATIO SELECTION FLOWCHART
- Is this for social media?
* Yes → Check platform-specific ratio
* No → Is this for print?
- Yes → Match print paper ratio
- No → 16:9 for most digital displays
6. COMMON MISTAKES TO AVOID
- Using 16:9 for vertical subjects (character looks small)
- Using 1:1 for wide landscapes (loss of context)
- Using default 1:1 for everything (lazy, inefficient)
INPUTS:
Intended use case:
[E.G., "Instagram carousel post for marketing"]
Platform (if applicable):
[E.G., "Instagram, YouTube, TikTok, LinkedIn"]
Orientation preference:
[PORTRAIT / LANDSCAPE / SQUARE / NO PREFERENCE]
Existing template dimensions (if any):
[E.G., "Canva template is 1080x1080"]
RULES:
- Always match platform native aspect ratio to avoid cropping
- 1:1 is safe but rarely optimal (except for Instagram feed)
- 16:9 is the web standard for horizontal content
- 9:16 is required for TikTok and Instagram Stories
- Print ratios must match paper dimensions exactly
- Consider safe zones for platforms that crop (e.g., YouTube thumbnails get cropped on mobile)
How To Use It
- Always match platform native aspect ratio to avoid cropping — don’t make platforms crop for you.
- 1:1 is safe but rarely optimal — except for Instagram feed posts.
- 16:9 is the web standard for horizontal content (YouTube, presentations, monitors).
- 9:16 is required for TikTok and Instagram Stories — vertical is not optional there.
- Print ratios must match paper dimensions exactly — you can’t crop print after the fact.
- Consider safe zones for platforms that crop (e.g., YouTube thumbnails get cropped on mobile).
Example Input
Intended use case:
“Marketing image for LinkedIn company page”
Platform:
“LinkedIn”
Orientation preference:
“LANDSCAPE”
Existing template dimensions:
“None”
Why It Works
Most users accept the default 1:1 square because they don’t know other options exist — or don’t know when to use them.
This framework improves outcomes by forcing:
- use case classification (social, print, presentation, web, video)
- platform-specific ratio mapping (Instagram vs. YouTube vs. TikTok)
- composition adjustment guidance (how framing changes by ratio)
- ratio selection flowchart (decision tree for non-designers)
- common mistake prevention (identifies frequent errors)
Failure modes this prevents:
- Square YouTube thumbnails (16:9 required, 1:1 gets black bars)
- Landscape Instagram Stories (9:16 required, crops to vertical)
- Portrait YouTube thumbnails (wrong orientation for platform)
- Mismatched print ratios (can’t crop without losing content)
This improves on: Default 1:1 habit. Platform-native ratios perform better and require no post-cropping.
Related to: MJ-01 (Parameters) for syntax; MJ-02 (Style Reference) for style consistency across ratios.
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