The short answer: a 15-second vertical ad needs a hook in the first second or two, one clear benefit, the product on screen, and a call to action, all readable with the sound off. Make it in 9:16 at 1080×1920 and keep text away from the edges where the app's buttons sit. With AI you write a short brief and get a draft in minutes, then refine it in plain words.
- Format: 9:16, 1080×1920, 15 seconds.
- Structure: hook (0–2 s) → benefit (2–9 s) → proof or product (9–13 s) → call to action (13–15 s).
- With Relo: 35 credits for the video and 10 for the render. Captions and music are free.
What makes a short vertical ad work?
In TikTok, Reels and Shorts, people decide whether to keep watching in about a second. The ads that hold them:
- Open with movement or a question, not a logo.
- Say one thing. Fifteen seconds is room for a single benefit.
- Work on mute. Big on-screen text and captions carry the message; sound is extra.
- Look native. A vertical, fast, text-led video blends into the feed; a resized TV ad doesn't.
What structure should a 15-second ad follow?
| Seconds | Beat | Example (a budgeting app) |
|---|---|---|
| 0–2 | Hook | "Where did my $400 go?" |
| 2–9 | Benefit | The app sorts last month's spending into categories automatically |
| 9–13 | Proof or product | The app screen with "Saved $120 this month" |
| 13–15 | Call to action | "Free on iOS and Android" + logo |
How do I write a hook that stops the scroll?
Hooks that work tend to be one of these:
- A question the viewer is already asking: "Still editing videos on a timeline?"
- A bold claim you can back up: "This app replies to your emails for you."
- A before/after: the messy version, then the clean result.
- A pattern break: something moving fast, or a big word slamming onto the screen.
Write three hooks for the same ad and make a version of each; it's the cheapest test you can run.
Where should text go in a vertical video?
Each app puts its buttons, captions and profile name over the video. Keep important text in the middle of the frame:
- Leave clear space at the bottom (the caption, username and call-to-action button live there).
- Leave clear space on the right edge (like, comment and share buttons).
- Keep the top of the frame free of key text too, since some apps overlay a header there.
Put titles and captions in the centre band, and on the last card put your logo and call to action well clear of the bottom edge.
How do I make one with AI?
- Write a brief of a few sentences: the product, the one benefit, the hook, the call to action, and "15 seconds, vertical".
- Turn on captions and pick a style. Bold, high-contrast styles suit fast ads; minimal styles suit calmer ones.
- Add music. Pick a mood (energetic or upbeat work for most ads).
- Watch the draft. Ask for changes in plain words: "Make the hook text bigger", "Cut the second scene", "End on the app store badges".
- Render in 9:16. If you also run feed ads, render 1:1 from the same video for 10 more credits.
An example brief:
15-second vertical ad for Penny, a budgeting app. Hook: "Where did my $400 go?" on a fast zoom. Show spending sorting itself into categories. End on "Free on iOS and Android". Energetic, bold captions, upbeat music.
Should I add a voiceover?
For ads, captions matter more than a voiceover, because many people watch on mute. Add a voiceover (+10 credits in Relo, from 21 voices) when the message is easier to say than to show, or for platforms where people tend to watch with sound on.
What does it cost?
| Item | Credits |
|---|---|
| The video | 35 |
| Render in 9:16 | 10 |
| Each extra hook variant (as an edit) | 5 |
| 1:1 version for feed ads | +10 |
| Captions, music, stock footage | Free |
Three hook variants and a final render come to about 55 credits. New accounts get 100 credits free; see pricing.
Sources
Sizes are from each platform's own ad specs: TikTok Ads help center, Meta Ads Guide and YouTube Shorts help. Checked 31 October 2026.
FAQ
What resolution should a TikTok or Reels ad be?
9:16, 1080×1920 pixels.
Can I make the same ad in square and horizontal too?
Yes. Relo renders one video in 9:16, 1:1 and 16:9; each size is a separate 10-credit render.
Should ads have captions?
Yes. Captions let the ad work on mute, and in Relo they're free.
Do I need footage?
No. Motion-graphics ads can be made from a brief alone. Add your clips or screenshots if you have them.