Keep only the part of the image you want. Drag the area while you look at it, and lock the ratio if you need one.
People crop for one of two reasons: to improve the composition, or because somewhere insists on a particular shape. The first is a judgement you make with your eyes; the second is a number you have to hit. Both are supported — drag the box where it looks right, or type the width, height and position directly.
Cropping without seeing what you are about to lose is guesswork. So everything outside the selection is dimmed, which makes the boundary between what you keep and what you discard obvious at a glance. Lock the ratio to 1:1 or 16:9 and every corner you drag keeps that shape.
Your original file is never modified. If the result is not what you wanted, move the box and cut again — each attempt starts from the original, not from the previous crop. That is why repeated cropping here does not degrade the picture step by step.
Everything runs inside your browser. Because the image never reaches a server, we cannot store it or look at it. That difference matters when the file is company material or a personal photo.