Pixels and crop are different.
Resize changes pixel dimensions. Crop changes which part of the image survives. Changing aspect ratio often means doing one, the other, or adding empty space.
Social & Ad Sizes
See how this banner might crop.
Stress-test the image in square, landscape, portrait and vertical shapes before you hand it to a platform.
1 Choose2 Check3 See answer
Useful to know
Four things worth knowing.
It cannot invent the frame.
A new shape cannot reveal content outside the original frame, and enlarging dimensions does not create genuine captured detail.
Check the edges.
Preview it at phone size and keep important text, faces and logos away from platform UI and edges.
Size for the destination.
Pick the final destination first. A profile photo, print, story and website hero all want different shapes for a reason.