What aspect ratio is
Aspect ratio is the proportional relationship between width and height. A 1200 × 800 image is 3:2; a 1000 × 1000 image is 1:1; a 750 × 1000 image is 3:4. Nothing about the ratio says how large the image is — only how its two sides relate.
Distortion appears the moment an image with one ratio is forced into different proportions without changing anything else. Squeezing a 3:2 photo into 1:1 narrows every face and widens every object. Nothing is lost — the picture is simply drawn at the wrong scale on each axis.
The two honest ways to fill an exact size
- **Crop** — cut away the parts that do not fit, keeping the remaining pixels undistorted. This is the right answer for portraits and ID photos: the subject stays natural, the frame becomes exact. Use Crop Image when you want to choose the cut yourself, or Exact Size Photo when you want the tool to fit and trim automatically.
- **Pad** — keep the whole image undistorted and add background around it until the dimensions match. Right for product shots and documents where nothing may be cut off. Product Square Image pads onto white or a chosen colour.
- **Stretch** — fill the target exactly and accept distortion. Sometimes correct for abstract backgrounds, almost never correct for faces, text or documents.
Checking before you commit
- Read the required dimensions and work out the ratio they imply — for example 35 × 45 mm and 210 × 270 px are both 7:9, while 35 × 45 mm and 413 × 531 px are also 7:9 but at a different scale.
- Compare that ratio with your source's ratio using Image Metadata on the original.
- If the ratios match, a straight resize with Resize Image will not distort anything.
- If they differ, decide between crop and pad before touching anything, then use the tool that does it deliberately.
- Inspect the result at full size: look at faces, text edges and any circle in the frame — those show distortion first.
Imagine a 1600 × 1200 photo that must be delivered at 1000 × 1000. Cropping keeps 1200 × 1200 from the centre and then scales to 1000 × 1000 — subject intact, sides trimmed. Padding scales the whole photo to 1000 × 750 and adds 125 px of background above and below — nothing lost, but the picture is smaller within the frame. Stretching to 1000 × 1000 fills the frame but makes everything about 33% too narrow. Only the first two keep the image honest.
When a requirement itself causes the problem
Some forms demand an exact width and height that does not match any normal photo ratio. That is not a reason to stretch — it is a reason to crop with the framing the authority expects, usually centred on the subject with headroom. If a photo is rejected for being the wrong shape rather than the wrong size, adjust the crop, not the scale. The passport and ID workflows in the photo workflow handle this in sequence.
Common questions
Does resizing by percentage ever distort?
No. Percentage and proportional resizing change both axes by the same factor, so the ratio is preserved. Only exact width-and-height sizing can distort.
Which is better for a form photo — crop or pad?
Crop. Forms expect the subject to fill the frame. Padding leaves coloured bands around the photo, which often fails a plain-background requirement.
Why does my photo look right-sized but still wrong?
Check the ratio against the requirement rather than the pixel count alone. Two images can share a dimension in one axis and differ wildly in the other.