Get the right aspect ratio and pixel dimensions for any AI image generator or social media platform. Covers Midjourney --ar flags, DALL-E presets, Stable Diffusion sizes, and all social formats.
The default Midjourney ratio is 1:1 (square). Use --ar 16:9 for landscapes, --ar 9:16 for portraits and Reels, --ar 3:2 for photos, and --ar 7:4 for cinematic widescreen. Add the flag to your prompt: /imagine a sunset --ar 16:9.
Instagram Reels use 9:16 vertical format at 1080×1920 pixels. Safe zone for text and UI is approximately 1080×1420 pixels in the centre. This is also the standard for TikTok.
SDXL works best at 1024×1024 for square images. For landscape: 1216×832 or 1344×768. For portrait: 832×1216 or 768×1344. Avoid non-SDXL sizes like 512×512 with SDXL models as quality degrades.
DALL-E 3 supports three sizes: 1024×1024 (1:1 square), 1792×1024 (16:9 landscape), and 1024×1792 (9:16 portrait). You cannot use custom sizes — choose the closest preset.
Instagram Stories are 1080×1920 (9:16). Keep important content in the centre 1080×1420 zone to avoid being covered by the profile bar (top 250px) and CTA buttons (bottom 250px).
Divide width by height and simplify to the smallest whole numbers. For example: 1920×1080 → divide both by GCD(1920,1080)=120 → 16:9.
Use --ar 3:2 (1216×832) for horizontal product shots, --ar 2:3 (832×1216) for vertical product cards, and --ar 1:1 for e-commerce listing thumbnails on Amazon and Etsy.