Aspect ratio is not resolution. An 800×800 image and a 2000×2000 image have different pixel counts, but both are 1:1. The ratio describes the shape of the frame; the resolution describes how many pixels fill it.
When the destination is known, set the ratio first and reduce the image to the required pixel dimensions afterwards. Starting with arbitrary dimensions can either stretch the image or cut off the part that matters.
Ratio and pixel dimensions answer different questions
A 16:9 ratio means that the frame is 16 units wide for every 9 units of height. Images measuring 1920×1080, 1280×720, and 640×360 all have the same shape. The larger versions simply contain more pixels, which gives them more room for large or high-density displays.
If you know the target width, divide it by the first ratio number and multiply by the second to find the height. At 16:9, a width of 1200 pixels gives a height of 675.
Common ratios suit different compositions
Do not choose a ratio simply because it is popular. Use the shape of the actual placement and the composition of the image. Platform recommendations can change, so check the current help page for the service before publishing.
| Ratio | Frame shape | Often useful for |
|---|---|---|
| 1:1 | Square | Icons, profiles, a balanced single subject |
| 4:3 | Landscape with more vertical room | Document captures, products, older digital photos |
| 3:2 | Traditional photo landscape | Camera photos, people shown with their surroundings |
| 16:9 | Wide landscape | Video thumbnails, headers, broad scenes |
A centred crop is not always the right crop
Automatic centre cropping works only when the subject is already near the middle. If a face sits to one side, or you plan to put text in the open space beside a product, move the crop manually.
A crop that looks fine in a large preview may lose more around the edges inside a mobile card or circular profile mask. Keep faces, logos, and embedded captions away from the edge of the safe area.
- Identify everything that must remain visible.
- Apply a crop frame with the target ratio.
- Leave useful space in front of a person’s gaze or around the main subject.
- Review the composition again at its real display size.
Make separate versions for different placements
Forcing one file into every frame with CSS leads to unpredictable cropping from one placement to another. For an important image, make separate square, landscape, and portrait versions.
Include the ratio and pixel size in the filename so the versions remain easy to identify. Names such as product-blue-1x1-800.webp and product-blue-16x9-1280.webp are more useful than final-2.webp.
Supported formats and export notes
GIF input and animated PNG or WebP files are not supported. Exports are re-encoded and may omit EXIF data, location, orientation information, and some colour profiles.
Keep the original instead of overwriting it in case you need a different crop later.
Example: make a 16:9 header from a 3:2 photo
You need to turn a 3000×2000 travel photograph into a 1200×675 website header while keeping a person on the left in frame.
Steps
- Open the 3000×2000 file in the PolishTools image resizer and cropper.
- Choose 16:9 as the crop ratio.
- Move the crop towards the left, leaving both the person and some space in the direction they are looking.
- Set the output dimensions to 1200×675.
- Check that the face remains clear in the preview, then export.
Result
The result is a 1200×675 still image that fills a 16:9 frame without distorting the person. Keep the source because the cropped areas above and below are not part of the export.
Frequently asked questions
Does a 16:9 image have to be 1920×1080?
No. Dimensions such as 1280×720 and 1200×675 are also 16:9. Choose the pixel count for the intended display size and quality.
Can I make a different ratio without empty space?
Yes, by cropping part of the source. If the whole picture must remain visible, you need padding or letterboxing. You cannot both keep everything and fill a differently shaped frame without distortion.
How do I decide where to crop?
Mark the faces, products, logos, or text that must remain. Then position the frame so it leaves useful space around the subject and in the direction of their gaze.