ShortslyUse 9:16 for a full-height vertical video, 4:5 for a shorter portrait frame, 1:1 for a square, and 16:9 for landscape. The numbers describe width compared with height, not image quality.
Choose the ratio before detailed editing. Changing it late can require new framing, new caption positions, and different motion paths for every scene.
In brief
- Choose the ratio from the primary publishing context, not from the shape of the first source file.
- Review every crop and motion endpoint after placing landscape or square media in a vertical frame.
- Keep a protected area for captions and interface overlays near the edges.
Understand what the aspect ratio controls.
The ratio does not specify a resolution by itself. A 9:16 project can be rendered at different pixel dimensions while preserving the same tall shape. Resolution affects detail; aspect ratio affects composition.
Every source image and clip must either fit, crop, or leave unused space inside the chosen canvas. The correct choice depends on the publishing destination and the way the audience will view the finished video.
Compare the four common project formats.
Scroll horizontally to compare every column.
| Ratio | Shape | Common use | Primary framing concern |
|---|---|---|---|
| 9:16 | Full vertical | Mobile-first short-form video | Landscape sources require substantial side cropping |
| 4:5 | Moderate vertical | Feed-oriented social posts | Top and bottom space is more limited than 9:16 |
| 1:1 | Square | Flexible feed and embedded placements | Wide scenes and full-body subjects may feel compressed |
| 16:9 | Landscape | Widescreen players and presentations | Vertical sources require side space or a deliberate crop |
Use 9:16 for a mobile-first vertical composition.
A 9:16 canvas gives a single person, product, or vertical illustration substantial presence on a phone. It also provides room to separate the main visual, captions, and a secondary foreground element.
Wide group photographs and landscape scenes need deliberate reframing. Do not rely on an automatic center crop when the important subject sits near an edge. Choose a different source, reposition the crop, or use the surrounding background as part of the composition.
Use 4:5 or 1:1 when the feed is the primary context.
A 4:5 canvas retains a vertical emphasis while requiring less height than 9:16. It works well for portraits, product demonstrations, and compositions that need a clear central subject. A square canvas is more neutral and can be useful when the same asset must appear in several embedded contexts.
Both formats provide less vertical separation than 9:16. Captions, faces, and foreground graphics can compete quickly, so reserve their positions early instead of fitting them into whatever space remains.
Use 16:9 when the viewing environment is landscape.
A 16:9 canvas supports wide scenes, side-by-side comparisons, screen recordings, and presentation-style layouts. A vertical portrait can still work, but it needs a planned background or supporting element rather than an arbitrary enlargement that removes the subject’s context.
Reframe subjects, captions, and motion safely.
- Set the project ratio before assigning detailed layouts.
- Inspect the start and end framing of every animated image or clip.
- Keep faces, product labels, quotations, and chart values away from risky edges.
- Check caption placement against both the scene composition and the destination interface.
- Preview the complete export at a realistic viewing size.
Run an aspect-ratio check before export.
Watch for empty edges, unintended crops, subjects entering the frame late, and captions that sit too close to an overlay area. Check transparent and green-screen assets at full frame size; a clean edge in one ratio may reveal unwanted source pixels after reframing.
Continue with the production workflow
Read the complete script-to-video guide or review the current editor controls and supported formats in Shortsly Help.