Crop or resize an image to fit a frame

Start with the source proportions

A 400 × 300 image has a 4:3 aspect ratio. A square frame has a 1:1 ratio. There is no way to fill that square with the whole source at unchanged proportions without either adding space, cropping or changing the frame.

Fit keeps the whole image

Fitting 400 × 300 inside 200 × 200 gives 200 × 150. Both target bounds are respected and the image remains proportional. The resizer does not silently add a square background around it. A destination may add its own padding when displaying the result.

Stretching to 200 × 200 fills both dimensions but changes proportions. The tool requires the aspect lock to be disabled before stretch can do that.

Crop chooses what remains

A crop at left 100, top 50, width 200 and height 200 produces a square selection from the original without resizing its pixels. Everything outside the rectangle is omitted. Drag on the preview for an initial selection, then use numeric coordinates to make it exact.

Fixed-ratio cropping derives height from width and rounds to whole pixels. Out-of-bounds rectangles produce an error; reduce the crop or move its top-left corner.

Choose based on the task

Use fit for documents and screenshots where all information must remain. Crop a photograph when composition can change. Stretch only when changing proportions is intentional. Enlarging adds interpolated pixels; it does not recover details absent from the source.

After editing dimensions, inspect output bytes and format separately. A square image can still exceed an upload byte limit. Keep the original so another composition can be prepared later.