01
What is the difference?
Aspect ratio is the relationship between width and height, such as 9:16, and it holds true at any size. Pixel dimensions are the actual count, such as 1080 by 1920. Many different pixel dimensions share the same ratio, which is why 720 by 1280 and 1080 by 1920 are both 9:16.
02
Same shape at different sizes
Four of these are the same shape and four different amounts of detail. Ratio decides what the clip looks like; pixel count decides how much is in it.
| Dimensions | Aspect ratio | Detail |
|---|---|---|
| 720 by 1280 | 9:16 | Least |
| 1080 by 1920 | 9:16 | Standard |
| 1440 by 2560 | 9:16 | More |
| 2160 by 3840 | 9:16 | Most |
| 1080 by 1350 | 4:5 | Different shape entirely |
03
Common sizes for each shape
For vertical 9:16, 1080 by 1920 pixels is the most widely used size. For 4:5, 1080 by 1350 is common, and for square 1:1, 1080 by 1080. For landscape 16:9, 1920 by 1080. Using these standard sizes avoids surprises when uploading, since platforms are built around them.
Smaller versions of the same shapes exist, such as 720 by 1280 for vertical, which keep the proportion but hold less detail.
04
Why the wrong ratio causes bars or crops
When a video's ratio does not match the space it is shown in, the platform either adds bars or crops the picture. A landscape video in a vertical feed usually appears with large empty areas above and below. A vertical video in a landscape player shows bars on the sides.
Matching the ratio to where the clip will be shown gives you control over what appears, rather than leaving it to the platform.
05
Working out a ratio from pixels
Divide width by height and compare with known ratios. 1080 divided by 1920 is 0.5625, which is 9:16. 1080 divided by 1350 is 0.8, which is 4:5. A calculator is enough, and it saves confusion when a file's properties show only pixel dimensions.
If the result does not match a common ratio, the file may have been cropped or exported with unusual settings.
06
Upscaling does not add detail
Exporting a small video at larger pixel dimensions makes the file bigger without making the picture sharper. The detail the camera captured is the limit. If a source is small, a clean export at its native size often looks better than an upscaled one.
Upscaling can be useful only when a platform requires a minimum size.
07
Keeping track of both
When describing a clip to a collaborator, mention both: vertical 9:16 at 1080 by 1920. Saying only 1080p leaves the shape unclear, and saying only 9:16 leaves the detail unclear.
Clear specifications prevent back-and-forth and re-exports.
08
Choose the shape, not the number
- Choose the ratio first. It decides what the clip looks like and what survives the crop.
- Let the pixel count follow. It is a consequence of the ratio and the delivery size.
- Never mix the two in one decision. Most confusion comes from treating them as one setting.
Pick a shape and run one clip in it. Nothing to pay for the first.
Questions people ask
- Can two clips share a ratio and look different?
- Easily. Same shape, different amounts of detail, because the pixel counts differ.
- Which matters more?
- The ratio, because it decides how much of your recording survives and how much screen you occupy. Detail is the second question.
- Do platforms care about pixel counts?
- They care about the shape, and they scale whatever they receive towards their preferred size. So the shape is what you control and the count largely follows.
- How do I work out the ratio?
- Divide width by height and compare. Working in named shapes rather than arithmetic is easier day to day.
- Which ratios are available here?
- 9:16, 4:5, 1:1 and 16:9, on every plan.