AI Video Aspect Ratio Guide: 16:9, 9:16 and More

Why Aspect Ratio Matters

Aspect ratio changes the composition the model must create. A landscape prompt has room for lateral movement and environment, while a vertical prompt favors full-body subjects, height, and movement toward or away from the camera. Choose the final publishing format before generating whenever possible.

Supported Formats

16:9 landscape

Use for conventional web video, presentations, desktop playback, and wide establishing shots. Place important action away from the extreme edges if the clip may later be cropped.

9:16 vertical

Use for short-form mobile feeds. Describe vertical composition explicitly: full-body framing, tall architecture, overhead-to-ground movement, or a centered subject with space for interface overlays.

1:1 square

Useful for flexible social placements, product loops, and compositions with a strong central subject. Avoid very wide camera moves that depend on horizontal space.

4:3 and 3:4

4:3 creates a classic landscape or archival feeling. 3:4 is useful for portraits, editorial fashion, artwork, and mobile placements that need more width than 9:16.

21:9 cinematic widescreen

Useful for landscapes, vehicles, side-to-side action, and dramatic negative space. Keep key subjects large enough to remain readable on smaller screens.

Composition Tips

• Mention where the subject appears: centered, left third, foreground, or distant background.
• Match camera movement to the frame: lateral tracking suits wide formats; approach and reveal work well vertically.
• Leave safe space if captions, buttons, or logos will be added in editing.
• Generate in the target ratio instead of relying on a heavy crop later.

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