YouTube Shorts 1080p and 100-character title: Sume's default fits

YouTube's Shorts page says a Short can be up to 3 minutes long, that the maximum resolution is 1080p, and that the title can be up to 100 characters. Sume Timeline's default 1080 x 1920 output already sits at that 1080p ceiling, so there is no reason to go higher for Shorts.

The figures come from YouTube's page (read 2026-10-10). The page does not state an aspect ratio rule in the version I fetched, so this post makes no ratio claim for Shorts.

What the page lists

The page gives these points for creating Shorts in the app: up to 3 minutes with the multi-segment camera, a title of up to 100 characters when you tap Next, an audience designation of made for kids or not, and a note that the maximum resolution is 1080p. It also says creators can upload pre-recorded vertical videos as Shorts. It mentions a change to how Shorts views are counted starting 3/31/2025.

Why a bigger render does not help

Timeline output edges accept even values from 256 to 2160. A 2160 x 3840 portrait file is not possible because 3840 is above the cap, and the page says Shorts tops out at 1080p anyway. Rendering 1080 x 1920 means the encoder works on fewer pixels and the file is smaller, with no loss against the page's own ceiling.

If you want a quick sanity check, the Timeline plan call is unbilled and returns the duration it computed, so you can confirm that a 3-minute cap holds before the render. A render costs $0.10 per output minute rounded up, so a 3-minute Short is $0.30 under the Timeline docs.

The title is not part of the video

The 100-character title is typed on YouTube. Sume has nothing to do with it, and it is not a good place for the AI disclosure either, because that is a separate setting on YouTube. If you also want visible text in the first seconds of the clip, Sume's video captions job can burn authored cues onto a public HTTPS video, with a style such as slam or punch.

Titles count characters, so check length including spaces. A title over the limit is a field you fix on YouTube, not a reason to re-render.

• Length: 3 minutes maximum.
• Resolution: stay at 1080p.
• Title: 100 characters maximum.
• Disclosure: set separately on upload.

A pragmatic export

For most generated Shorts, render with Timeline at the default 1080 x 1920 with cover fit, keep the audio spine under 180 seconds, and trim only if a source clip is longer. Do the upload in the app or on desktop, set the title and audience, and answer the altered content question honestly.

Because the page does not state an aspect ratio rule, I would not guess one. In practice Shorts are vertical, and a 9:16 render at 1080 x 1920 is the format Timeline produces by default, so the safest approach is to keep vertical and let YouTube show it as it does. If you need to verify what the app expects, check the upload screen itself before a large batch.

For batches, loop over your finished files and check three numbers before upload: duration under 180 seconds, frame size 1080 x 1920 or below, and title under 100 characters. All three are cheap to check in code and expensive to find out about after a failed upload.