AI Shorts Maker
One topic → a 9:16 mp4 in minutes. ViralMint writes the script, generates AI voiceover, burns word-by-word captions and exports 9:16, 16:9 and 1:1 in one run — Shorts, TikTok, Reels and YouTube long-form covered without re-rendering.
What's an AI shorts maker?
An AI shorts maker produces short-form vertical videos (9:16, typically 30-60 seconds) for YouTube Shorts, Instagram Reels and TikTok with minimal manual editing. The five hard parts — script, voiceover, visuals, captions, music — are all AI-generated or auto-assembled from a single topic prompt. ViralMint runs all five steps from one topic, then bundles the output in three aspect ratios (9:16, 16:9, 1:1) so the same video can be posted on Shorts, TikTok, Reels, YouTube long-form and Instagram feed without re-rendering.
Vertical-format mechanics matter. A Short isn't a long video cropped to 9:16 — the hook lives in the first 1.5 seconds, the payoff has to land before second 25 to keep retention, and captions are non-negotiable because 70% of viewers watch muted. ViralMint's AI script writer is tuned for short-form retention curves, and the caption burn step uses Whisper word-level timestamps so every spoken word lands on the exact frame — no two-second-late "captions" that kill the hook.
How to make an AI short in 5 steps
- Type a topic. "3 mistakes new investors make", "why Tesla earnings missed", "iPhone 17 features Apple didn't announce" — anything that fits a 60-second short. Or paste a competitor's YouTube/TikTok URL to learn from.
- Pick the format. 9:16 vertical for Shorts / Reels / TikTok is the default. Toggle multi-aspect export to ALSO get 16:9 (YouTube long-form) and 1:1 (Instagram feed) in the same run — no re-rendering.
- Choose voice + tier. 21 paid OpenAI voices (gpt-4o-mini-tts) or 400+ free Edge TTS voices across 100+ languages. Free tier uses Pexels stock; paid tiers (Sora 2 Pro, Veo 3.1, Seedance, Hailuo 2.3, Wan 2.7) generate actual AI video clips per scene.
- Generate. 11-step pipeline runs in the background — script, voiceover, Whisper transcription for caption timing, clip generation or stock search, stitching, music mix, caption burn (viral / classic / bold presets), thumbnail extraction, AI-drafted Shorts title and TikTok caption. 3-6 min on stock, 8-15 on premium AI-video.
- Post on all three platforms. Multi-aspect export ZIP gives you 9:16 for Shorts/Reels/TikTok, 16:9 for YouTube long-form, 1:1 for Instagram feed. AI-drafted titles, descriptions and tags ready to copy-paste when uploading.
What makes ViralMint different for Shorts
Multi-aspect export bundle
One generate run → 9:16, 16:9 and 1:1 in a single ZIP. Most AI shorts makers re-render each aspect separately at full cost. ViralMint reuses the source clips and re-frames at the FFmpeg layer, so the multi-aspect bundle adds seconds, not dollars.
Hook-aware script writer
The AI script writer is tuned for short-form retention curves: hook in 1.5s, problem statement by 8s, payoff by 25s, CTA by 45s. Uses competitor transcripts when you give it a reference URL.
Word-level caption sync
Whisper word-level timestamps + ASS subtitle rendering means every word lands on the exact frame. Three presets — viral (yellow highlight, Montserrat Bold 56pt), classic (Arial 42pt), bold (Impact 64pt green).
Trend-aware topic picking
Don't have a topic? Pair the Shorts maker with ViralMint's trending video finder to pull breakout topics from YouTube, TikTok, Douyin and Reddit, scored by channel-baseline outlier multiplier.
Stock or AI b-roll per scene
Free tier: Pexels stock keyword-matched per script line. Paid tier: Sora 2 Pro / Veo 3.1 / Seedance generate the actual moving clips, or Nano Banana generates b-roll images from script prompts.
Free background music
Free uploaded music library or AI-generated tracks via Lyria 3 Pro (~$0.05 / 30s). Auto-mixed at -20dB with fade-in/out so the voiceover stays the focus.
Shorts, Reels, TikTok — same video, three platforms
Posting on all three short-form platforms from one source video is the lowest-effort, highest-leverage move a creator can make. The video format is identical (9:16, 30-60s), the audiences overlap less than you'd think, and platforms reward cross-posting because they can see the video performed elsewhere. ViralMint's multi-aspect export ZIP gives you a 9:16 mp4 (works on all three) plus a 16:9 horizontal cut (YouTube long-form) plus a 1:1 square (Instagram feed) — three formats from one generate run.
The AI-drafted metadata is also platform-aware: ViralMint generates a YouTube title (under 60 chars, hook-led), description (with chapters if the video is long enough), tags, plus a separate TikTok caption (under 150 chars, hashtag-aware, first-line-hook for the "more" expand fold). Copy-paste when posting — no auto-upload (kept manual on purpose).
Frequently asked
What does an AI shorts maker do?
An AI shorts maker is a tool that produces short-form vertical videos (typically 9:16, 30-60 seconds) for YouTube Shorts, Instagram Reels and TikTok with minimal manual editing. It usually handles the script (AI-written from a topic), the voiceover (AI text-to-speech), the visuals (stock footage or AI-generated clips), the captions (auto-synced word-by-word), and the music (royalty-free or AI-generated). ViralMint runs all five steps from one topic prompt — typical end-to-end time is 3-6 minutes for stock-footage tier, 8-15 minutes for premium AI-video tier.
Can ViralMint export to YouTube Shorts and Instagram Reels at the same time?
Yes. One generate run produces a 9:16 vertical mp4 ready for YouTube Shorts, TikTok and Reels. The multi-aspect export bundle wraps that 9:16 plus a 16:9 horizontal version (for YouTube long-form) and a 1:1 square (for Instagram feed / Facebook) into a single ZIP. No re-rendering, no separate generate runs — three platforms covered in one click.
Is the AI shorts maker free?
The stock-footage tier is free: Pexels stock matched to your script, Edge TTS voiceover (400+ free voices, 100+ languages), word-by-word captions, FFmpeg merging — all running on your desktop with no per-video cost. Premium tiers swap stock for AI-generated video clips (Sora 2 Pro, Veo 3.1, Seedance), add AI b-roll imagery (Nano Banana), or AI music (Lyria 3 Pro); these cost a few cents to under a dollar per video, billed per use via prepaid top-ups — no subscription.
How long should an AI short be?
For YouTube Shorts and TikTok, 30-60 seconds is the sweet spot — long enough to land a payoff, short enough that the algorithm rewards completion rate. Instagram Reels currently caps at 90 seconds but most viral Reels are under 30. The ViralMint AI script writer defaults to 45-55 seconds for 9:16 output unless you specify otherwise in the prompt.
Can ViralMint generate Shorts in languages other than English?
Yes. Edge TTS covers 100+ languages free — Spanish, Portuguese, Mandarin, Japanese, German, French, Korean, Arabic and more — with multiple voices per language. The AI script writer accepts any target language. Captions render Unicode cleanly (Chinese, Japanese, Arabic, Hebrew). The Whisper transcription used for caption timing supports 99 languages, so caption sync is correct in every language without per-language tuning.
Make your first AI short
Sign up takes 30 seconds. The browser version covers AI chat, AI image, AI voice and AI music — same balance as the desktop app. The full Smart Video pipeline ships in the free desktop app.