Correction, 2026-10-02: an earlier version said no single generation on 8frame runs longer than 30 seconds. That holds for text- and image-to-video, but the talking-avatar tools OmniHuman 1.5 and Pruna Avatar run to 35 seconds. It also said every video model on 8frame offers 9:16, which is too broad for tools that follow an input image (the page now names the models), left out that Merge Videos takes 2 to 10 clips and trims each one to at most 15 seconds (5 by default), dated the three-minute rule "after" October 15, 2024 where YouTube says "on or after", and did not say that Shorts thumbnails can only be added on a computer. All YouTube figures were re-checked on 2026-10-02. It also did not say that the file Merge Videos makes has no sound; step 4 now says so and sends music and voice to the Video Editor timeline.
Correction, 2026-10-01: an earlier version said Kling offers 9:16 when generating from text, without saying which Kling. On 8frame, Kling v3 needs a start image and follows its shape; 9:16 from text alone is Kling 2.6 Pro.
A YouTube Short can be up to three minutes long, as long as the video is square or vertical. YouTube Help puts it plainly: "You can now create YouTube Shorts up to three minutes in length", and videos uploaded on or after October 15, 2024 with a square or vertical aspect ratio and up to three minutes long are treated as Shorts. The old 60-second limit, which YouTube's own Shorts help page still gave in September 2024, is out of date. For AI video, three minutes means joining clips: no text- or image-to-video generation on 8frame runs longer than 30 seconds.
TL;DR
| Spec | YouTube Shorts |
|---|---|
| Maximum length | 3 minutes |
| Shape | square or vertical |
| Counts as a Short if | uploaded on or after October 15, 2024 (December 8, 2025 for Official Artist Channels), square or vertical, 3 minutes or less |
| Longer than one minute | blocked worldwide while it has an active Content ID claim |
| Custom thumbnail | 2160 x 3840 (9:16), at least 640 px tall, verified accounts, added in YouTube Studio on a computer |
From YouTube Help, "Understand three-minute YouTube Shorts" and "Add custom thumbnails on YouTube", checked 2026-10-02.
Building a long Short from AI clips
The longest single text- or image-to-video generation on 8frame is 30 seconds (Wan 3.0 and Seedance 2.5); only the talking-avatar tools, OmniHuman and Pruna Avatar, run to 35 seconds, and their length follows an audio track. Kling v3 and Hailuo H3 stop at 15, Veo 3.1 at 8. A three-minute Short is therefore six 30-second clips or, more usually, many shorter shots cut together.
A workable structure for a 60 to 90 second Short:
- Hook, 2 to 3 seconds. One striking shot. Generate several and keep the best.
- Body, 6 to 10 shots of 5 to 8 seconds. Short shots are cheaper to redo than one long take.
- Payoff, one shot. The reason to watch to the end.
- Join them. Merge Videos on 8frame joins 2 to 10 clips for 10 credits, but trims each clip to a maximum length you set between 1 and 15 seconds (5 by default), so raise it before you run, and its merged file has no sound. For music or voice, more than 10 clips or a full three minutes, lay the shots out on the timeline of 8frame's Video Editor, which has sound layers, or in any editor.
Draft every shot at 480p in 9:16 (24 credits for 5 seconds on Wan 3.0), then regenerate the keepers at 720p (48) or 1080p (95). Each model's length limits are in clip length limits by model.
One rule before you pass a minute: YouTube blocks worldwide any Short longer than one minute that has an active Content ID claim, so clear the music first. YouTube says royalty-free tracks from its Audio Library do not receive a Content ID claim.
Square or vertical?
Both count as Shorts. Vertical 9:16 fills a phone screen; square works when the same video also goes to feeds that crop to 1:1. Wan 3.0, Seedance 2.5, Veo 3.1 and Hailuo H3 all offer 9:16 from a text prompt. On Kling, 9:16 from text is Kling 2.6 Pro; Kling v3 needs a start image and follows its shape, and Wan 3.0 and Hailuo H3 also follow the shape of a start image when you give them one, so start from a vertical image. Choosing a model for Shorts is covered in best AI video generator for YouTube Shorts.
The thumbnail
YouTube recommends 2160 x 3840 for Shorts thumbnails, at least 640 pixels tall. Custom Shorts thumbnails need a verified account and can only be added in YouTube Studio on a computer. Full requirements in YouTube thumbnail size.
FAQ
How long can a YouTube Short be? Up to three minutes, if the video is square or vertical, per YouTube Help.
When did YouTube Shorts go to three minutes? Videos uploaded on or after October 15, 2024 that are square or vertical and up to three minutes long are treated as Shorts. For Official Artist Channels the date is December 8, 2025.
Is a 16:9 video under three minutes a Short? No. Shorts must be square or vertical; YouTube suggests a wider ratio such as 16:9 for videos you do not want classified as Shorts.
How do I make a three-minute Short with AI? Generate shots of 5 to 30 seconds in 9:16 and join them. No text- or image-to-video generation on 8frame is longer than 30 seconds, and Merge Videos takes up to 10 clips of up to 15 seconds each, so use the Video Editor timeline for the full three minutes.
Sources
- YouTube Help, "Understand three-minute YouTube Shorts": "You can now create YouTube Shorts up to three minutes in length"; square or vertical; uploads on or after October 15, 2024 (December 8, 2025 for Official Artist Channels); Shorts longer than one minute with an active Content ID claim blocked globally; Audio Library tracks receive no Content ID claim; a wider ratio such as 16:9 to avoid Shorts classification: support.google.com/youtube/answer/15424877, checked 2026-10-02
- YouTube Help, "Get started creating YouTube Shorts", in September 2024: Shorts "up to 60 seconds long": archived copy of 2024-09-02, checked 2026-10-02
- YouTube Help, "Add custom thumbnails on YouTube": 2160 x 3840 for Shorts, minimum height 640 pixels, verified accounts, Shorts thumbnails only in YouTube Studio on a computer: support.google.com/youtube/answer/72431, checked 2026-10-02
- 8frame clip lengths, aspect ratios and prices (Wan 3.0 2 to 30 s at 24 / 48 / 95 credits per 5 s, Seedance 2.5 4 to 30 s, Kling v3 3 to 15 s, Hailuo H3 5 to 15 s, Veo 3.1 up to 8 s, OmniHuman 1.5 and Pruna Avatar up to 35 s, Merge Videos 2 to 10 clips trimmed to 1 to 15 s each for 10 credits): the 8frame app, checked 2026-10-02; Video Editor timeline: the 8frame app, checked 2026-10-02; no audio track in the Merge Videos output: the 8frame app, checked 2026-10-02
- Kling v3 start-image requirement: the 8frame app, checked 2026-10-01
Hook, body, payoff, joined.
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