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Social Media Optimizer

Specs, formats and what actually moves reach

The formats, specs and diagnostics — without the invented statistics

Which aspect ratios actually matter, where the interface covers your text, what hashtags do now that discovery is recommendation-driven, and how to work out why your reach fell. Reference material, kept dated.

Five ratios cover everything

Per-platform size tables are longer than they need to be. Collapse the duplicates and there are five shapes worth producing — and most content plans need three of them.

9:16
Stories, Reels, TikTok, ShortsFull-screen vertical video everywhere.
4:5
Instagram, Facebook and LinkedIn feedsThe tallest still image a feed will show without cropping.
1:1
Every feed, and profile gridsThe safe default when one asset has to work in several places.
1.91:1
Link previews on Facebook and LinkedInComes from the page's Open Graph image, not from the post.
16:9
YouTube thumbnails, X in-streamThe only landscape ratio still worth producing.

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