Social Image Sizes: Cropping, Formats and Compression

A campaign image rarely fits every destination unchanged. Square feed posts, portrait cards, vertical stories and landscape thumbnails use different aspect ratios, so exporting one file at several pixel dimensions is not enough. The composition must be reconsidered whenever the shape of the frame changes.

Start from the destinations that matter, not from a generic list of dimensions. Platform recommendations can change, but the underlying workflow remains stable: choose the target aspect ratio, protect the subject and essential text, then export enough pixels for the intended display without creating unnecessary file weight.

Resizing changes the number of pixels while preserving the full composition and its aspect ratio. Cropping removes parts of the image to create a different frame. Stretching an image to force a new ratio distorts faces, typography and products, so it should not substitute for a deliberate crop.

When moving from landscape to portrait, select a crop focus around the information that must survive: a face, product, headline or action. Check the edges at normal viewing size. A mathematically centered crop is not always a visually correct crop.

JPEG is broadly compatible and efficient for photographs, but repeated exports accumulate compression damage and it does not preserve transparency. PNG is useful for transparency, diagrams and sharp interface graphics, although photographic PNG files can become unnecessarily large. WebP often provides smaller photographic or mixed-content files at comparable visual quality in modern workflows.

Format is only one part of the decision. A high-quality export can still look poor if it has been cropped badly, enlarged beyond the useful detail in the source or compressed again by the destination platform.

Keep one high-quality editable master. Create each aspect ratio from that master instead of transforming a previously compressed social export. Name files by platform and placement, then inspect the final pixel dimensions at 100% and at approximate phone size.

Compression should be judged visually around text, faces, gradients and high-contrast edges. Reduce quality gradually until the file-size benefit begins to produce visible artifacts, then step back. Retain the master so future platform changes do not require rebuilding from a degraded derivative.