YouTube Shorts generator: vertical AI videos built to hold attention
YouTube Shorts are vertical videos of up to three minutes, discovered mostly through the Shorts feed. The first two seconds decide whether a viewer swipes away, so Shorts live or die by the hook, the pacing and on-screen captions.
ShortsMachine writes hook-first scripts, generates every scene in 9:16, and adds narration and captions automatically, so each Short is ready to upload.
Shorts settings that work
| Setting | Recommendation |
|---|---|
| Format | 9:16 vertical |
| Length | 30–60 seconds for most topics; up to 3 minutes for stories |
| Hook | A question, bold claim or surprising visual in the first scene |
| Captions | Always on — many viewers watch muted |
| Ending | Loop back to the start, ask a question, or tease the next video |
Writing Shorts that get watched to the end
- Open in the middle of the action, not with "Hi guys" or a slow intro.
- One idea per Short. If you have five facts, consider five Shorts.
- Change the visual every few seconds — ShortsMachine’s scene-by-scene approach does this naturally.
- End with something that rewards watching again or following.
Which models suit Shorts
For daily Shorts, Wan 2.2 Fast and HeyGen Video 1 keep costs low. For Shorts that need to stand out visually, Grok Imagine, FLUX 3 Max, Kling 3.0 or Seedance give smoother motion. All of them output vertical video; MiniMax H3 is landscape-only, so it is not offered for 9:16.
Frequently asked questions
What resolution are the Shorts?
Vertical videos are exported at 720×1280 (HD) at 30 fps, which YouTube accepts and plays back sharply on phones.
Can I upload the same video to TikTok and Reels?
Yes. The same 9:16 file works on YouTube Shorts, TikTok and Instagram Reels, with no watermark on paid plans.
How long can a YouTube Short be?
YouTube allows Shorts of up to three minutes in a vertical or square format. ShortsMachine can generate up to 5 minutes, so keep Shorts at 3 minutes or less.
Make your first video in a few minutes
Type an idea and ShortsMachine writes the script, generates every scene, adds a voiceover and captions, and stitches it into one video — up to 5 minutes long.
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