When a destination asks for exact pixel dimensions, first compare its shape with your image. A 2400 × 1600 photo has a 3:2 ratio. Resizing it to 1200 × 800 preserves that shape; forcing it into a 1080 × 1080 square changes the proportions unless you crop or add padding.
Image Resizer offers proportional fitting, centered cropping and exact dimensions. Padding is a separate option in Canvas Padding and Square Fit. Choose the behavior that preserves the parts of the picture you need.
Decide what may happen to the edges
| Method | Whole picture retained? | Exact target box? |
|---|---|---|
| Fit inside | Yes | Output can be smaller than the box on one side |
| Fill and crop | No; centered overflow is trimmed | Yes, when the enlargement setting permits it |
| Exact with aspect lock | Yes | The other dimension follows the source ratio |
| Exact without aspect lock | Yes, but proportions can change | Yes |
| Canvas padding | Yes | Yes, with space around the picture |
Use Fill when losing some background is acceptable. Use padding when the edges contain people, text or product details. Exact without aspect lock is suitable only when the requested width and height already match the source shape, or distortion is intentional.
Use proportional Exact output correctly
In Image Resizer, choose Exact size and enable Keep the original aspect ratio. Set the width or height you must meet and check the Aspect reference. The helper follows the first selected image while you edit the dimensions, but each exported image uses its own source ratio.
For a 2400 × 1600 image, a reference width of 1080 gives a height of 720. That is proportional, but it is not a square. Changing both requested numbers to 1080 cannot keep the original shape without cropping or padding.
Exact without aspect lock needs both dimensions. With the lock on, the other side can be derived from the reference. Exact applies the requested or derived size even when Allow enlarging smaller images is off, so check a small source before requesting a much larger output.
Fit, Fill and Percent respect the enlargement setting. With enlargement off, Fill can reduce an oversized target box instead of producing its full dimensions. Turn enlargement on only if you accept the loss of apparent detail, or choose a larger source.
Make a square without stretching
For the 2400 × 1600 photo and a 1080-square requirement, two useful routes are:
- Crop: choose Fill and crop with 1080 for both dimensions. The centered crop removes side content while keeping the remaining subject in proportion. If the subject is off-center, use Image Cropper first to choose a better square crop, then resize it.
- Pad: choose the 1080-square preset in Canvas Padding and Square Fit. It fits the photo down without cropping, producing a 1080 × 720 picture inside the square, with 180 pixels of space above and below when centered.
Choose a solid, transparent or blurred padding background as appropriate. Transparency needs PNG or WebP; JPEG uses opaque padding. A frame adds an outer band and increases the final dimensions, so leave frames off when the destination requires exactly 1080 × 1080.
Check dimensions and file limits separately
Image Resizer accepts up to 20 JPEG, PNG or WebP files, 64 MiB each and 128 MiB together. Each input and each output canvas is limited to 40 megapixels. Width and height individually accept up to 20,000 pixels, but a 20,000-square image would contain 400 megapixels and is not allowed.
The same settings apply to a batch. If images have different shapes or need different crop positions, use separate runs rather than expecting one set of numbers to suit all of them. Aspect Ratio Calculator can help calculate a proportional missing dimension.
Pixel dimensions do not determine the encoded file size. JPEG and WebP quality can change both the bytes and fine detail; PNG ignores quality. A JPEG/WebP Target size is a measured, best-effort encoding attempt, not a guarantee that a destination will accept the file.
Inspect the actual result
Check the download's width and height, then look at circles, faces and lettering for distortion. Confirm that the crop kept important edges or that padding has the intended color and transparency. Enlarging a soft source cannot restore missing detail.
When using Social Media Image Resizer, treat named presets as convenient pixel boxes and compare them with the destination's current requirements. The destination may crop or re-encode an upload after you send it. Keep an original so you can make another version without repeatedly editing an already reduced copy.