Formats & specs
Aspect ratio: definition and examples
What is Aspect ratio?
Aspect ratio is the proportional relationship between a video's width and its height, expressed as two numbers separated by a colon, such as 16:9, 1:1, or 9:16. For short-form social video, the ratio you choose determines whether your content fills a phone screen or appears with black bars on the sides or top.
Reference: social media video sizes for every platform
Aspect ratios by platform
| Platform / placement | Aspect ratio | Pixels |
|---|---|---|
| TikTok | 9:16 | 1080 × 1920 |
| Instagram Reels | 9:16 | 1080 × 1920 |
| YouTube Shorts | 9:16 | 1080 × 1920 |
| Instagram feed (portrait) | 4:5 | 1080 × 1350 |
| Instagram feed (square) | 1:1 | 1080 × 1080 |
| YouTube (landscape) | 16:9 | 1920 × 1080 |
When you'd use it
- 1When choosing which platform to publish a video on and need to match its native format.
- 2When a video shot in landscape needs to be repurposed for a vertical-first feed.
- 3When placing text or graphics and need to know how much horizontal space is available.
- 4When a video appears letterboxed or pillarboxed on a specific platform and you want to fix it.
- 5When briefing an editor or motion designer on output specs.
Example
A brand films a product demo with a mirrorless camera in 16:9 at 1920x1080. When the editor exports and posts the file directly to TikTok, the platform displays it with black bars on both sides, giving the video a desktop-video feel in a vertical feed. Re-exporting at 1080x1920 (9:16), cropped to keep the product centered, removes the bars and fills the viewer's screen.
Use cases
- 1Exporting the same clip in 9:16 for Reels and 1:1 for feed posts.
- 2Reframing a 16:9 interview to 9:16 so the speaker fills the vertical frame.
- 3Checking a template's aspect ratio before dropping in brand footage.
FAQ
What is the difference between aspect ratio and resolution?
Aspect ratio describes the shape of the frame (the proportion of width to height). Resolution describes how many pixels fill that shape. A 9:16 frame can be 1080x1920 or 720x1280; the shape is identical, but the pixel count and resulting sharpness differ. Changing resolution does not change the aspect ratio, and vice versa.
Make on-brand short-form video from the footage you already have.