Requirement guide
Keep text and the primary subject inside the central safe area so the post still reads in compact previews.
The 1200 × 1200 starter canvas is useful for a square LinkedIn post where the primary message needs room around it. Fit with padding is safer for designs with edge text; crop is useful when the source already has a strong central composition.
The source filename and source bytes are not the output. Aftermath reports the final dimensions, format, and measured bytes, so you can catch a wrong export before attaching it to a post or scheduling workflow.
Questions people ask
No. It prepares a local, correctly named image and leaves publishing in your control.
Yes. Choose PNG or WebP and a transparent background when the destination supports it.