Midjourney Aspect Ratio Calculator
Get the exact --ar parameter for your next Midjourney prompt — pick a preset or enter a custom width and height.
--ar 1:1
AI generation sizes
Wallpaper sizes
Print sizes (300 DPI)
Social media sizes reference
Sizes used across major platforms, for context when picking your ratio:
| Platform & placement | Recommended size | Ratio |
|---|---|---|
| Instagram feed post (square) | 1080 × 1080 | 1:1 |
| Instagram portrait post | 1080 × 1350 | 4:5 |
| Instagram / TikTok Story or Reel | 1080 × 1920 | 9:16 |
| YouTube thumbnail | 1280 × 720 | 16:9 |
| Facebook shared image | 1200 × 630 | 1.91:1 |
| X (Twitter) post image | 1600 × 900 | 16:9 |
| LinkedIn post image | 1200 × 627 | 1.91:1 |
| Pinterest Pin | 1000 × 1500 | 2:3 |
How the Midjourney Aspect Ratio works
Choose a ratio
Pick a common preset like 16:9 or 1:1, or type in any custom width and height.
Toggle orientation
Switch between landscape and portrait to flip the ratio instantly.
Copy dimensions or --ar
Grab the exact pixel dimensions from the tables, or copy the ready-made Midjourney --ar parameter.
About this tool
Midjourney's --ar parameter accepts whole-number width:height ratios and defaults to 1:1 (square) if you don't specify one. Common choices are 16:9 for landscape/widescreen shots, 9:16 for portrait/mobile compositions, and 3:2 for a photography-style frame.
Use this calculator to pick a preset or enter any custom dimensions, then copy the ready-made --ar parameter straight into your Midjourney prompt — no need to manually simplify the ratio yourself.
Remember that --ar sets the shape of the output, not its resolution; Midjourney determines final pixel dimensions based on your chosen model version and any upscale step.
Frequently asked questions
What is the default Midjourney aspect ratio?
Midjourney defaults to 1:1 (square) if you don't add an --ar parameter to your prompt.
What is the maximum aspect ratio range in Midjourney?
Midjourney v5 supports ratios up to 2:1, while v6 and later versions extend support up to 3:1 for more extreme, cinematic compositions.
Does --ar affect image resolution?
No, --ar controls the shape (width-to-height ratio) of the output, not the final resolution, which depends on the model version and any upscaling.
Other aspect ratio tools
Writing the prompt itself? Try the Prompt Character Counter →