Social Preview Checker & OG Image Debugger

Why check your social preview before publishing?

A broken or missing preview image, a mismatched title, or a conflicting tag between Open Graph and Twitter Card metadata can make a shared link look unfinished or untrustworthy -- and by the time you notice, it may already be cached by the platform that shared it. Checking first means you can fix a problem before it reaches an audience, not after.

This tool fetches the actual page server-side (a browser cannot read another site's HTML directly because of cross-origin restrictions), parses its real HTML, and inspects the resolved preview image itself rather than trusting the declared dimensions.

What this tool checks, and how

• Open Graph. The protocol's four required base properties (og:title, og:type, og:image, og:url) plus the structured og:image sub-properties and og:description/og:site_name, which are recommended but not required.
• Twitter/X Card. twitter:card, twitter:title, twitter:description, twitter:image, twitter:site and twitter:creator, cross-checked against the Open Graph equivalents. X documents that it falls back to Open Graph tags when a twitter:* tag is missing, so a missing tag is reported as informational, not an error.
• Canonical & URL relationships. The requested URL, the final URL after redirects, the declared canonical, and og:url are compared -- a mismatch is reported as a fact, never as a claim about search ranking or indexing.
• The actual preview image. Fetched and inspected directly: real HTTP status, content type, and pixel dimensions read from the image's own header bytes, compared against any declared og:image:width/height.

What this tool cannot promise

• It cannot guarantee exact platform rendering. Facebook, X, LinkedIn and other platforms may cache a previous version of a page's preview, apply their own crawler logic, or change layouts without notice. The previews shown here are simulations built from the metadata this tool could fetch, not a call to any platform's own API.
• It cannot guarantee search ranking or indexing outcomes. A canonical mismatch is reported as a fact; this tool never claims to know how Google will index a URL.
• It only reads the page once, as a logged-out, non-JavaScript visitor would. A page that renders its metadata with client-side JavaScript will not show those tags here, since the fetch never executes the page's scripts.

Privacy

SkyyCast fetches the public URL you submit, server-side, to inspect its HTML and social metadata. The submitted URL necessarily reaches the SkyyCast API to do this -- we do not claim this tool works entirely in your browser, because that would not be true for a tool that reads another site's page. We do not require your site's credentials, do not forward cookies or an Authorization header to the page being checked, do not execute its JavaScript, and do not store the analysis, the fetched HTML, or a copy of the image anywhere after the response is returned.

More free tools

See all free SkyyCast tools. Publishing to Bluesky? Check the post first with the Bluesky Post Validator, or the image with the Bluesky Image Size Checker.

About this tool

SkyyCast is an independent third-party service. It is not affiliated with, endorsed by or sponsored by Facebook/Meta, X, LinkedIn, or any other platform referenced on this page. Platform names are used only to describe the preview format being simulated.