Coordinates, not vibes: making the box match the brief
Portals, ad servers, and LMS uploaders often reject a file that is “almost” the right size. 1079×1080 can fail a 1080×1080 rule. This page is for numeric honesty: you lock both dimensions, place the rectangle, and the export is those integers — or you see immediately that the source does not contain enough pixels and you should not upsample mush. Canvas coordinates start at the top-left. X grows to the right, Y grows down. A selection is left, top, plus the two edge lengths in source pixels. Nudging by a few pixels matters when a face sits on a hard crop line or when Open Graph images must keep a logo inside 1200×628. Common targets: 1080×1080 for many feed tiles and app icons, 1920×1080 for Full HD slides and 16:9 heroes, 1200×628 for classic Facebook-style link previews. LinkedIn and other networks publish their own pixel lists; treat those as checklists, not as “close enough.” Cropping is still not resizing. If the source is 6000×4000 and you only need a 1200×628 region, you are choosing which 1200×628 window to keep. If you need the whole scene squeezed into 1200×628, that is a scale operation — Image Resizer — and it will change how large objects appear. Photographers shooting for marketplaces should frame first at native resolution, then scale down so the listed size is met without interpolating up. Retina UI sometimes wants 2× the CSS size (a 400×400 avatar slot may ask for 800×800). Read the spec. HEIC still needs a decode-to-JPG or PNG pass before integer crops are reliable in the browser. Windows, Mac, and Linux sessions share this same Canvas path.