AI Video Generator for YouTube Shorts

Most people searching for a Shorts generator already have the footage — a podcast, a webinar, a long vlog — and need it turned into vertical clips. That is what Clip Studio does end to end: it downloads your source, measures the real duration with ffprobe, extracts mono 16 kHz audio, transcribes it with word-level timestamps, has an LLM pick the strongest self-contained moments, then cuts each one, centre-crops it to 1080×1920 and burns word-timed captions into the frame.

The moment picker is explicit about what it will and won't do. Each clip must be 10–75 seconds, must not overlap another clip, must start at the beginning of a sentence and end at a natural stopping point — never mid-sentence. It returns a title, a hook line and a 1–10 virality score per clip, and if the source genuinely doesn't contain enough good moments it returns fewer clips rather than padding with weak ones.

If you don't have source footage, the same 9:16 output is reachable two other ways: Creator Reel builds a captioned 1080×1920 talking-head short from a topic and one photo, and any of the 54 video model variants can generate a fresh vertical clip from a prompt.

Open Clip Studio

What this tool does

  • YouTube treats a vertical upload as a Short when it runs 3 minutes or less; Clip Studio caps every clip at 75 seconds, comfortably inside that limit.
  • Clip Studio renders 1080×1920 h264+aac with word-timed ASS captions burned in, cut from the original audio's word-level transcript rather than an estimated timing track.
  • One Clip Studio job returns 1 to 5 clips (default 3), each 10–75 seconds long, each starting and ending on a sentence boundary and never overlapping another clip.
  • Clip Studio accepts sources up to 90 minutes and 1.5 GB, and costs 2 credits per source minute with a 4-credit minimum per job.
  • Clip Studio re-measures your source with ffprobe after download and charges only the difference if the reported duration was short — you are billed on the real length, not the claimed one.
  • Every Clip Studio clip comes back with an AI-assigned title, a hook line and a 1–10 virality score, and the tool returns fewer clips rather than padding a thin source with weak moments.
  • Creator Reel produces a 1080×1920 captioned short from a topic plus one photo, in 30-second, 1, 1.5 or 2-minute lengths, and can also output a 16:9 master of the same edit in the same job.
  • Gemini Omni is the 4K option for vertical: 4, 6, 8 or 10 seconds at 720p, 1080p or 4K, in 16:9 or 9:16 only — it has no square mode.
  • Seedance 2.5 is the longest single generation available at 4–30 seconds (480p or 720p); Vidu Q3 reaches 16 seconds with audio; most other models cap at 15 seconds per job.
  • Free-plan downloads carry a VdoBloom watermark; a paid plan downloads the identical render watermark-free.

How it works

  1. 1.Give Clip Studio your long video

    Point it at a podcast, webinar, interview or vlog. The hard limits are 90 minutes of runtime and a 1.5 GB download; anything longer or larger is rejected before you are charged.

  2. 2.Choose how many Shorts you want

    Set the clip count between 1 and 5 (the default is 3) and leave captions on. Cost is calculated from the source length at 2 credits per minute with a 4-credit floor, so a 40-minute podcast is 80 credits regardless of how many clips you ask for.

  3. 3.Let the transcript drive the cuts

    Audio is transcribed with word timestamps, then an LLM reads the timestamped transcript and picks non-overlapping moments of 10–75 seconds that start at the beginning of a thought and end at a natural stop. It scores each pick 1–10 for virality.

  4. 4.Collect the vertical renders

    Each chosen moment is cut, centre-cropped to 1080×1920 and re-encoded with word-timed captions burned in. The first clip becomes the primary result; the rest are attached to the same job so you can download them all.

  5. 5.Fill the gaps with generated Shorts

    If you need more Shorts than the source can support, switch to Creator Reel for a scripted captioned short from a topic and one photo, or generate from scratch with any 9:16-capable model.

Frequently asked questions

How long can a YouTube Short be?

YouTube's Shorts rules treat a vertical upload of 3 minutes or less as a Short (the limit was 60 seconds before an October 2024 change, so verify the current rule in YouTube's own help pages). Clip Studio caps every clip at 75 seconds, which sits inside the limit either way. Creator Reel offers finished lengths of 30 seconds, 1, 1.5 and 2 minutes.

Does Clip Studio add captions automatically?

Yes. It transcribes the clip audio with word-level timestamps and burns the captions into the 1080×1920 frame as ASS subtitles, so the words land on the syllable rather than on an estimate. Captions can be turned off if you'd rather add your own in YouTube Studio.

What does it cost to clip a one-hour podcast?

2 credits per source minute with a 4-credit minimum, so a 60-minute source is 120 credits whether you ask for 1 clip or 5. The duration is re-measured server-side with ffprobe after download — if the length reported by your browser was short, only the difference is charged.

Why did I get fewer clips than I asked for?

By design. The highlight picker is instructed to return fewer clips rather than pad a thin source with weak moments, and it discards any candidate that overlaps a higher-scoring one or that is shorter than 10 seconds. A source with little speech or heavy silence will legitimately yield 1 or 2 clips.

Can I make Shorts without existing footage?

Yes. Creator Reel writes a script from a topic, films it as a run of 4–15 second talking clips using your photo, and burns in kinetic captions — output is 1080×1920. Or generate a single fresh clip on any model that exposes 9:16, including Runway, Kling V3 Turbo, Seedance, Wan 2.7, PixVerse, Vidu, SkyReels V4, Gemini Omni and Veo 3.1.

Can I get a 16:9 version for the main channel at the same time?

Creator Reel can. If you set it to 16:9 it returns four files from one job — 9:16 captioned, 9:16 clean, 16:9 captioned and 16:9 clean — so the Short and the long-form upload come from the same render. Set it to native 9:16 and it returns two files: captioned and clean.

Is 4K possible for vertical?

Gemini Omni renders 4K in 9:16 at 4, 6, 8 or 10 seconds. Separately, Topaz Video Upscale can take an existing render up to 2× or 4×, billed per second of source video.

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Ready to try it?

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