An AI YouTube Shorts Generator That Posts for You

Mediasynth generates, captions, and publishes YouTube Shorts on your schedule — across seven character-driven formats built for the share-and-comment dynamics Shorts actually rewards. Set up a premise once, ship daily Shorts forever.

200 free credits on signup · No credit card required

Built for Shorts, Not Repurposed for It

Most "AI video" tools generate horizontal corporate video and crop it to 9:16. Mediasynth's seven formats are designed vertical-first for the Shorts feed.

Tier list

Comment-bait by design — viewers pause to argue your rankings, which spikes Shorts retention.

Quiz

Forces a watch-to-end pause for the answer; the algorithm reads that as completion.

Reddit story

Hook-front-loaded narratives that ride the AITA / TIFU subgenre that already dominates Shorts.

Dialogue

Two characters debating cuts the "talking head fatigue" that kills Shorts watch time.

Skit

Character-driven scenes feel native to Shorts, unlike straight-to-camera AI avatars.

Rant

High-energy single-character monologues optimized for the 7-second hook window.

Text messages

Vertical-native conversation format that reads naturally on mobile-first Shorts viewers.

The Posting Workflow

Connect your YouTube account once via OAuth. Define a premise — the topic source, character cast, format mix, and posting schedule. From there, Mediasynth writes scripts, generates voices and animations, syncs word-level captions, and uploads each finished Short to YouTube on your schedule. No daily logins, no per-video manual work, no exports to download.

The same premise can also publish to TikTok, Instagram Reels, and Facebook Reels from the same render. One premise, four platforms, on schedule.

Set It Up Once. Let It Run Forever.

Start with 200 free credits. No credit card required. No daily work.

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