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OG image too small for social previews

Social platforms have opinions about OG image sizes. Miss the recommended dimensions and your preview looks broken.

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What this usually means

Your page declares an og:image, but the image is smaller than the platform minimum (often less than 600 pixels wide), has an unusual aspect ratio, or is oversized beyond the platform cap (often more than 5 MB). As a result, previews on Slack, LinkedIn, X, Discord, and Facebook crop badly, shrink the image, or render a small thumbnail variant instead of the large preview card.

Why it matters

A poorly sized OG image reduces click-through rate on shared links and makes your brand look unpolished. Large preview cards with a proper image perform visibly better on every social surface. Platforms also cache previews aggressively, so a bad first render can stick around for days.

Common causes
  • og:image points at a 200x200 logo or favicon instead of a dedicated preview.
  • The image is exactly 1200 pixels wide but squished into a 600x315 aspect ratio, triggering small-card fallback.
  • The file size exceeds platform caps (many platforms time out above 5 MB).
  • The URL points at a private CDN or a path that returns 404/403 for unauthenticated fetchers.
  • The image uses a non-standard content-type (e.g. image/webp where the platform wanted image/png or image/jpeg).
  • twitter:image is missing and falls back to a default small card.
How to diagnose it
  1. Open OG Preview and paste the page URL.
  2. Check the resolved og:image URL and the image probe: status, content-type, width, and height.
  3. Look at the rendered preview card to see how it fills the space.
  4. Confirm the image is publicly reachable (no login wall, no hot-link protection).
  5. Check twitter:image as a secondary probe for X, LinkedIn, and some chat platforms.
How to fix it
  1. 1

    Target 1200x630 pixels

    Use 1200x630 (roughly 1.91:1) as the default. Most major platforms render a large card at that size. Avoid square or very narrow aspect ratios for primary previews.

  2. 2

    Keep the file under 5 MB

    Compress the image so it stays under 5 MB. Aim for 500 KB where possible. Use JPEG or PNG, not WebP, for maximum platform compatibility.

  3. 3

    Host the image publicly

    Serve og:image from a URL that returns 200 with an image content-type, no auth, no hot-link protection, no bot blocking, and a CDN that allows non-browser clients.

  4. 4

    Set twitter:image and twitter:card

    Add twitter:card = summary_large_image plus twitter:image. Without these, X falls back to the small card even if og:image is correct.

  5. 5

    Force a refresh on caching platforms

    Use platform debuggers (Facebook Sharing Debugger, LinkedIn Post Inspector, Twitter Card Validator) to refresh the cache after fixes, otherwise old previews persist.

FAQ
What size should an OG image be?

1200x630 pixels, roughly 1.91:1. That is the safe default for Facebook, LinkedIn, Slack, Discord, and most other platforms, and it also renders correctly on X when paired with twitter:card = summary_large_image.

Why does my image crop badly?

Different platforms crop to slightly different aspect ratios. Designing for 1200x630 with a safe centered area (around 1080x550) keeps the main content visible across every platform crop.

How do I refresh cached previews?

Use the official platform debuggers. Facebook has Sharing Debugger, LinkedIn has Post Inspector, X has Card Validator. Each one fetches the URL fresh and clears the cached preview, so the updated og:image appears next time the link is shared.

Related fixes

Ready to diagnose your URL?

OG Preview runs the exact checks discussed above.

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