Grok Imagine publishes seven shapes and a default

The docs list 1:1, 16:9, 9:16, 4:3, 3:4, 3:2 and 2:3, with 16:9 as the default. Four rows in this column publish a default at all, and five name a square option; this row does both. As of 2026-09-22.

Inclusion rule. Ratios the aspect ratio parameter accepts on this page, with the default it names. A shape offered in a consumer interface but absent from the parameter list is not recorded. Order. The list, then the default inside it, then the notable absence.

1Seven values with nothing conditional attached

The shape list here carries no dependence on resolution, duration or model variant. Combined with a one to fifteen second range and a three rung ladder that are equally unconditional, this row publishes the fewest interactions between columns of any entry in the register.

That is what makes it easy to plan against and unremarkable to read. Every combination the three lists allow is a combination the page supports on its face, so the only work left is choosing.

2Widescreen as a default, for a product that is mostly vertical in use

Sixteen by nine is the stated fallback, which matches the Masthead and not the feed surfaces where short-form advertising mostly runs. A vertical campaign has to set the field on every request, and one that forgets gets a usable file in the wrong shape.

Three other rows in this column default the same way and one defaults to adaptive. Where a default exists at all in this register it is horizontal, which says these parameters were designed around a widescreen assumption rather than around where the ads run.

3No ultrawide, which two other rows do publish

Twenty-one by nine is absent here and present on three other entries. Nothing in the advertising formats this register reads asks for it, so the gap costs nothing against a placement and matters only for reuse outside one.

The register records absences at this level of detail because the shape column is the one that cannot be fixed later. A missing tier is a quality compromise; a missing shape is a piece that has to be generated again somewhere else.

4Where this cell sits in the column

Inclusion rule. Every generator in the register, carrying whatever its own page says about output shape. Six rows say nothing and are marked hollow rather than dropped. Order. Alphabetical by generator name.

• Aspect ratio parameter
  1:1, 16:9, 9:16, 4:3, 3:4, 3:2 and 2:3, with 16:9 the defaultxAI docs, video generation / recorded 2026-09-22
• Resolution parameter
  1080p, 720p and 480p, with 480p the defaultxAI docs, video generation / recorded 2026-09-22

5Sources

Read from the xAI video generation docs, checked 2026-09-22. The column itself is described on aspect ratio, and the rule that keeps surfaces and generators apart is on method. Next along this column: HeyGen, Hedra.