Pinterest max-width video from a 9:16 master: the 1:1 height limit

Pinterest says max-width video cannot exceed the height of a 1:1 aspect ratio, so a 1080x1920 vertical master has to be reshaped. In a Sume timeline render with output 1080x1080, fit cover keeps 56.25 percent of the rows (1,080 of 1,920), while fit blur shows the whole frame as a 608-pixel-wide picture on a blurred fill.

What Pinterest lists

Max-width video ads expand across the feed on mobile and are paid-only.

The two ways to reshape a vertical master

The page does not give a pixel size for max-width video, so choose 1080x1080 as the tallest allowed at that width. Timeline 1.0 accepts even sizes from 256 to 2160.

1080x1920 source into 1080x1080, computed 2026-10-09, as listed below.

• cover: working Scale 1.0 by width; 1,920 rows cropped to 1,080; result 56.25% of rows kept (1,080 / 1,920)
• contain or blur: working Scale 1,080 / 1,920 = 0.5625; width 1,080 x 0.5625 = 607.5; result Picture about 608 wide, 472 columns of fill
• stretch: working Both axes fitted; result Whole frame, squashed

Choosing

Cover is right when the subject sits mid-frame, since it loses the top and bottom 420 rows (1,920 - 1,080 = 840, split in two). Blur is right when text or a logo is near the top or bottom. A wider shape such as 16:9 is also allowed, because 1920x1080 is shorter than 1:1, and needs no reshaping from a landscape master.

• Timeline render: $0.10 per output minute, rounded up (Sume catalog, read 2026-10-08).
• A 15-second ad is 1 minute, so $0.10.
• Run the unbilled plan endpoint first to check the document compiles.

Checking the output

Probe the render with video inspect and frames false. Read width and height and confirm that height is not greater than width. Also read duration_seconds against the 4 second minimum and 15 minute maximum, and video_codec against H.264 or H.265.

Then extract one still and look at the crop. In cover mode, check that heads and text are not cut at the top or bottom edge; in blur mode, check that the fill does not distract from the picture. Both checks take a few seconds and avoid a rejected upload.

Why not keep the vertical file

A standard-width Pin accepts vertical video, and the same 9:16 master works there. The 1:1 limit applies to the max-width format only, which is why you render a second file for it instead of changing the master.

Cost scales with length, not with the shape. A 30-second max-width render is 1 minute at $0.10, and a 60-second render is also 1 minute. At 61 seconds the render is 2 minutes and $0.20 (Sume catalog, read 2026-10-08). Since Pinterest recommends 6 to 15 seconds, most files bill at the 1-minute minimum.

Keep the 1080x1920 master. It serves the standard-width placements with no change, and you only render the square from it when you book max-width.