SceneMixer names a default shape and one alternative

The site states sixteen by nine as the default with nine by sixteen available. Two shapes with a named default is the minimum that lets a plan proceed, and it is more than most priced pages in this register publish. As of 2026-10-13.

Inclusion rule. Shapes this vendor states on its own site. A shape reachable by cropping in an editor is not a published output shape and is not recorded. Order. The default first, then the stated alternative.

1Two shapes is enough for the formats that exist

Of the six YouTube formats this register reads, only the Masthead carries a stated shape, and it is widescreen. Everything vertical runs on feed and Shorts surfaces. Two shapes covering both cases answers the placement question this site was built to ask.

Where it stops is square. The one platform here that publishes a square option states one by one at 640x640 or more, and this page names nothing between its two values, so that route is not confirmable from the source the rest of the row was read from.

2A named default is a commitment about the unspecified case

Most pages in this column list shapes without saying which one arrives if nobody asks. This one does, which means a pipeline that omits the field produces widescreen rather than something a reader has to guess at.

For vertical advertising the default is the wrong way round, and knowing that is the point. A brief for a feed placement has to set the field explicitly, and a batch of variants generated without it will come back in the shape the other placement wanted.

3Shape is the axis a clip ceiling cannot rescue

Length problems are solved by an edit: more pieces, more joins, more time. A shape problem is solved by generating again, because cropping a widescreen frame to vertical moves the subject out of the picture rather than merely tightening it.

That is why this register puts shape in its own column even though vendors publish it far less often than resolution. On this row both are stated on the same page as the clip ceiling, which is unusual among the priced pages here and is the reason the row can be planned against at all.

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 ratios
  16:9 by default, with 9:16 availablestated on the sitescenemixer.com / recorded 2026-09-19
• Longest single generation
  30 seconds on the Wan 3.0 and Seedance 2.5 tiers, 15 seconds on the Seedance 2.0 and MiniMax H3 tiersstated per tierSceneMixer, price list / recorded 2026-10-13

5Sources

Read from the SceneMixer site, checked 2026-10-13. The column itself is described on aspect ratio, and the rule that keeps surfaces and generators apart is on method. Next along this column: Google Veo, MiniMax.