Social Media Poster Size and Design Guide for 2026

A social media poster has to survive fast scrolling, platform cropping, and small-screen reading. The safest workflow is to design around a clear center, one primary message, and enough quiet space around the edges.

Recommended poster sizes

• Instagram feed: square or portrait works best, with important text away from the top and bottom edges.
• Instagram Stories and Reels covers: keep the headline in the center safe area.
• LinkedIn posts: use a professional layout with a short headline and one supporting visual.
• Pinterest pins: portrait designs often perform better because they occupy more vertical space.

What to include in the prompt

• Mention the platform and intended crop, such as "Instagram portrait post" or "LinkedIn announcement graphic".
• Specify the hierarchy: headline first, then product or visual, then CTA.
• Ask for readable typography and generous margins.
• Use style words like minimalist, modern, bold, retro, or vintage only when they support the brand.

Common mistakes to avoid

Avoid tiny paragraphs, multiple CTAs, heavy texture behind text, and visuals that depend on details near the edge of the image. Social media posters usually work best when they feel like one strong idea rather than a compressed brochure.