The quick answer
YouTube currently categorizes videos uploaded after October 15, 2024 as Shorts when they use a square or vertical aspect ratio and are no longer than three minutes. You can upload through the YouTube app or YouTube Studio.
A 9:16 export is the clearest default for a full-screen mobile experience. Square videos can qualify, but they do not use the same amount of vertical screen space.
Recommended dimensions
Exporting at 1080 by 1920 pixels gives you a standard 9:16 vertical HD canvas. Keep important faces, captions, and demonstrations away from the extreme edges because interface controls can compete with content near the sides and bottom.
Do not add black bars
YouTube advises creators not to add black bars to vertical videos. Let the platform fit the video to the viewer’s screen. If your original footage is horizontal, reframe around the active speaker or important action rather than shrinking the entire landscape frame into a vertical canvas.
How long can a YouTube Short be?
For standard channels, a square or vertical upload can be categorized as a Short when it is up to three minutes long. A shorter limit is not automatically better: the right length is the shortest version that preserves the setup, useful detail, and payoff.
There is an important music consideration. YouTube states that a Short longer than one minute with an active third-party Content ID claim can be blocked globally. Creators using music should review YouTube’s current eligibility rules before publishing longer Shorts.
Shorts export checklist
- Use a 9:16 vertical canvas unless a square format is intentional.
- Export at 1080×1920 for a practical full-HD result.
- Keep the finished video at three minutes or less.
- Remove black bars and reframe the subject for vertical viewing.
- Keep captions readable and inside comfortable safe margins.
- Watch the complete export on a phone before uploading.
- Check music rights carefully when the Short is longer than one minute.
9:16 · 1080×1920 · one clear idea · captions inside safe margins · no black bars.