Start with a decoded 1200×800 ordinary photo and select 1:1 while the crop covers the full image. The largest square that fits has side 800. Vertical space is already exact; 400 horizontal pixels must be removed, split evenly as 200 on each side.

Verify the four fields

The centered crop must read X=200, Y=0, width=800 and height=800. Exporting without further movement creates an 800×800 file. Moving the square changes X or Y but never its 800×800 size while it remains inside the source.

Check content, not just dimensions

The numbers prove geometry, not composition. Inspect whether the subject remains comfortably framed and reposition the square if needed. CropFrame makes no automatic face, subject or safe-area decision.

Keep the crop in its proper scope

CropFrame creates a new Canvas-decoded image and does not preserve metadata, provenance, measurements or evidentiary fidelity. Use it for ordinary digital publishing and design. Do not use it to prepare identity, medical, legal, inspection, emergency, navigation or other safety-critical imagery, and independently verify every important result.