A portrait crop can suit a head and shoulders photo, a tall product, or a workplace detail. It is less useful if the meaning depends on a wide group or a piece of equipment that stretches across the scene. Before resizing, decide what the reader should understand from the image and make sure that context survives the vertical frame.
The 1080×1350 preset is our preparation choice for a 4:5 post image. It is not a claim that every LinkedIn image must use those dimensions. Link previews, article covers, and company banners are separate placements, and an image attached directly to a post should be prepared for its own composition.
For event photographs, check people near the sides rather than centring automatically on the speaker. A crop that removes a colleague or half a product can change the meaning of a photograph. Use an original proportion export when the whole scene matters more than filling a tall frame.