Can a YouTube Shorts series episode be square? Render 1080x1080
Yes. YouTube's Shorts series rule says portrait or square, up to 180 seconds. How to render a square episode with Sume Timeline output width, height and fit.

Does a Shorts series accept square videos?
Yes. YouTube's shows page says a Shorts series playlist must contain only Shorts, and that the videos must be portrait or square in dimension with a maximum duration of 180 seconds. Landscape is the shape to avoid.
So 1080x1080 is a valid choice for a series, and so is the default 1080x1920. Pick one for the whole season so the show looks the same from episode to episode.
| Shape | Allowed in a Shorts series | Sume Timeline setting |
|---|---|---|
| Portrait | Yes | Default 1080x1920 |
| Square | Yes | output.width 1080, output.height 1080 |
| Landscape | No, per the rule | Avoid |
Rendering square on Sume
Timeline 1.0 defaults to 1080x1920. To change it, send output.width and output.height as even integers between 256 and 2160. Every video slot then needs a fit that suits the source: cover (the default) fills the frame and crops, contain keeps the whole picture with bars, blur fills the bars with a blurred copy, and stretch distorts.
Imagery planned for portrait often loses its top and bottom in a square crop, so check the framing on the first episode before you batch the season.
curl -X POST https://api.sume.com/v1/timeline-1.0/render \
-H "Authorization: Bearer $SUME_API_KEY" \
-H "Content-Type: application/json" \
-H "Idempotency-Key: show-s1-e01" \
-d '{
"audio": {"url": "https://media.sume.com/artifacts/artf_demo/voice.wav",
"duration_seconds": 40},
"output": {"width": 1080, "height": 1080},
"video": [{"source_url": "https://media.sume.com/artifacts/artf_demo/clip.mp4",
"start": 0, "duration": 40, "fit": "cover"}]
}'Cost and checks
The assembly rate is $0.10 per output minute, rounded up, so a 40-second square episode bills one minute. Call the unbilled plan endpoint first to see the duration and estimated cost. All source URLs must already be media.sume.com files in your workspace, since the API rejects off-host links.
Do not mix shapes inside one show without a reason. A feed viewer sees each Short on its own, but a show page puts them in a row, and one square episode among portrait ones looks like a mistake unless it is intentional.
If you are unsure which shape to commit to, render the first episode both ways with the unbilled plan call and one paid render each, then compare them on a phone. At one billable minute apiece the test costs twenty cents, which is cheap next to re-rendering a season after you notice the crop.
- Choose one shape per season.
- Use blur only if you accept the blurred bars.
- Keep each episode at or under 180 seconds.
Sources
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