Stretching an image into a new ratio instead of cropping or padding, which makes products look wider or taller than they are.
Resolution and scaling
Aspect ratio
Also called image ratio, width to height ratio or 1:1 4:5 16:9. Here is what it means, when it changes what you export, and what people get wrong.
Resolution and scalingRuns on your deviceUpdated 10 August 2026
The short answer
Aspect ratio is the relationship between an image's width and its height, written as two numbers such as 1:1, 4:5 or 16:9. It describes shape, not size: 1000 x 1000 and 3000 x 3000 are both 1:1. You change it by cropping pixels away or padding with background.
Updated
The short version
Aspect ratio at a glance
| Quick fact | Detail |
|---|---|
| Written as | width:height, for example 4:5 |
| Describes | Shape only, never pixel count |
| Marketplace default | 1:1 square |
| Meta catalog | 1:1, recommended 1024 x 1024 px |
| Phone camera default | Usually 4:3 |
| Two valid ways to change it | Crop away, or pad out |
Slide the table sideways to see every column.
How do you work out the ratio of an image?
Divide both dimensions by their greatest common factor. A 1600 x 1200 px image divides by 400 to give 4:3. A 1080 x 1350 px image divides by 270 to give 4:5. If the numbers do not simplify neatly, divide width by height and compare the decimal: 1:1 is 1.00, 4:5 is 0.80, 3:2 is 1.50 and 16:9 is about 1.78. Width always comes first, so 4:5 is a tall image and 5:4 is a wide one.
Which ratios come up in practice?
| Ratio | Width / height | Example size | Where you meet it |
|---|---|---|---|
| 1:1 | 1.00 | 2048 x 2048 px | Marketplace product images, profile pictures |
| 4:5 | 0.80 | 1080 x 1350 px | Tall social feed posts |
| 4:3 | 1.33 | 4032 x 3024 px | Most phone cameras by default |
| 3:2 | 1.50 | 6000 x 4000 px | Most mirrorless and DSLR cameras |
| 16:9 | 1.78 | 1920 x 1080 px | Video, banners, wide screens |
| 9:16 | 0.56 | 1080 x 1920 px | Full-screen vertical video |
Cameras hand you 4:3 or 3:2, and almost every product listing wants 1:1, so a ratio change is part of nearly every ecommerce export.
Crop or pad: which one should you use?
Cropping cuts pixels off the long edge to reach the target shape. It keeps every remaining pixel at full quality but loses content, which is fine for a product on a plain backdrop and painful for a tightly framed lifestyle shot. Padding adds background to the short edge instead, keeping the whole frame but making the subject smaller within it. On a white background, padding is invisible and is usually the right answer for product shots.
Whichever you pick, do it with a crop or a canvas extension, never by stretching. Photomop's crop tool holds a fixed ratio while you position the frame, which is the quickest way to keep a set of listing images consistent.
What happens if you upload the wrong ratio?
The platform decides for you, and rarely the way you would. Most storefronts centre-crop a non-square image into a square tile, so a product framed edge to edge loses its sides, and a model's head can lose its crown. Others letterbox instead, adding bars that make your listing look smaller than the competition in a grid. Meta's catalog guidance asks for square 1:1 at a recommended 1024 x 1024 px for exactly this reason. Deliver the shape the platform wants and you keep control of the composition.
What people get wrong about aspect ratio
Each one is a real failure mode, not a style preference.
Framing tight to the product, then uploading to a platform that centre-crops to square and clips the edges off.
Reading 1:1 as a pixel size, when 500 x 500 and 5000 x 5000 are equally square.
Questions people ask
Aspect ratio, answered
The follow-up questions people search for once they have the definition.
What aspect ratio should product photos be?
Square, 1:1, for almost every marketplace. Meta's catalog guidance specifies square images at a recommended 1024 x 1024 px, eBay's recommended 1600 x 1600 px is square, and Etsy's guidance of at least 2000 px on both sides points the same way. Export square once and it travels well.
Is 4:5 the same as 5:4?
No. Width is always stated first, so 4:5 is taller than it is wide and 5:4 is wider than it is tall. Swapping them turns a portrait crop into a landscape one, which is a common cause of images arriving rotated or badly cropped.
How do I make a photo square without cutting the product?
Pad rather than crop. Extend the canvas on the short edge with the same background colour, keeping the product centred. On a white backdrop the join is invisible. If the background is textured, replacing it with a plain colour first makes padding seamless.
What aspect ratio is 1920 x 1080?
16:9. Both numbers divide by 120 to give 16 and 9, a width to height figure of about 1.78. It is the standard shape for video and wide screens, and a poor fit for product listings, which almost always expect square.
Same cluster
More from the glossary
Neighbouring entries, so every term in the set is one hop from every other.
AVIF
AVIF stores AV1-coded pictures inside a HEIF container.
Alpha channel
An alpha channel is an extra layer of information in an image file that records how see-through each pixel is.
Background removal
Background removal separates the subject of a photo from everything behind it and discards the rest, leaving either a transparent cut-out or the subject on a new backdrop.
From the studio
Tools that do this
Each one runs on your own device, so the photo stays where it is.
Sources
Where the facts on this page come from. Every link opens the specification, standard or documentation the claim was read at.
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