Video
Aspect ratio
Aspect ratio is the width-to-height proportion of a frame: 16:9 for widescreen and YouTube, 9:16 for vertical shorts, 1:1 for square feeds, 21:9 for cinema. In AI generation it is a parameter on modern engines and a prompt hint on older ones.
Choosing the ratio at generation time matters because a vertical composition is not a cropped horizontal one — the engine frames the subject for the format. Product pages want 16:9, TikTok and Reels 9:16, feeds 1:1.
On eroq
Video offers six ratios — 16:9, 9:16, 1:1, 21:9, 4:3 and 3:4. All six are native on the Seedance and Hailuo engines; Grok Imagine and Wan 3.0 take all but 21:9, Kling the first three, and Veo and Runway 16:9 and 9:16, while Motion One takes 16:9, 9:16, 1:1, 4:3 and 3:4. Images: 1:1, 3:4, 4:3, 9:16 and 16:9.
Questions
Can AI video be vertical?
Yes — 9:16 is native on Seedance, Veo, Kling, Hailuo, Runway, Wan and Grok. Motion One takes 16:9, 9:16, 1:1, 4:3 and 3:4.
What aspect ratio should I use for TikTok?
9:16, picked before the render rather than cropped afterwards — the engine composes a vertical frame instead of trimming a horizontal one. Feed posts want 1:1, YouTube and product pages 16:9.
What happens if an engine does not support my ratio?
The ratio is folded into the prompt instead, and an engine that insists on a native value gets the nearest one — 21:9 and 4:3 fall back to 16:9, 3:4 to 9:16. Nothing fails; the framing is steered rather than set.
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