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Free tools / 饾晱 card validator

饾晱 card and link preview validator

Enter the address of a page you are about to share. The validator reads the tags its link preview is built from, twitter:card, the title, the description and the image, shows which tag each one came from, and gives you a line of HTML for each one that is missing.

Updated

Crux reads up to the first 1 MB of the page, for at most 5 seconds. The image itself is not downloaded.

The tags a link preview is built from show here, with a fix for each one missing.

Crux's server fetches the page you enter, only over https and only from a public address, reads up to its first 1 MB, and sends back the tags it found, not the page. Each result is kept in memory for 10 minutes, and to limit checks your network is counted for an hour by a keyed hash of its address, also only in memory. Nothing is written to a database.

How it works

A link preview on 饾晱 is built from tags in the page's <head>: twitter:card chooses the layout, and the title, description and image come from twitter: tags or, without them, from Open Graph tags (og:title, og:description, og:image). This validator fetches the page, reads those tags and lists what is missing, such as an image, an image description or one of the four tags the Open Graph protocol requires, with the tag to paste. It reads the tags; it does not show the card exactly as 饾晱 will draw it.

Questions

Why does my link show no image on 饾晱?

Usually because the page has no twitter:image or og:image tag, or the tag gives a relative address. The validator flags both and gives the full tag to paste.

Which tags does 饾晱 read?

twitter:card for the layout, and twitter:title, twitter:description and twitter:image, falling back to the Open Graph tags og:title, og:description and og:image. The validator shows which tag each value came from.

Does it check the image size?

No. It does not download the image. On 19 October 2026 饾晱's developer site no longer had its card markup reference, so the validator quotes no image limit it could not check.

Which pages can it read?

Public https pages on the usual port. It refuses addresses on private networks, follows at most 3 redirects and checks each one the same way, and stops after 1 MB or 5 seconds. Pages behind a login show only what they show a visitor who is signed out.

From one post to every push

Crux (cruxpost.com) watches the GitHub repos you choose. Each push, merged pull request or release becomes three drafts in your voice, checked the way this site鈥檚 tools check a post, and your coding agent can add why a change matters through the Crux plugin for Claude Code and Codex. Crux reads commit messages, pull request and release text and the names of changed files, never a diff. Post on copies the draft you like and opens with it, for you to post; on Autopilot, Crux posts only what you schedule. It reads each post at 1 hour, 24 hours and 7 days, and learns which kinds of post work for your account only once a pattern beats chance.

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