Open graph preview: check the launch link before anyone shares it
Networks keep the first card they build, so founders should preview the link with seogeoaeo.ai's checker, fix the tags, then set each platform's cache.
An open graph preview is the card a link becomes on LinkedIn, Facebook, Slack or X, seen before anyone posts it. For a founder it is a five-minute check with a long tail: networks keep the first card they build, so a launch link with no picture or a clipped title can carry that mistake through the day that matters most. We run every launch URL through seogeoaeo.ai's link preview checker before it goes out, then set the platform caches.
Why the first share decides the card
The cache rules come from the networks' own documentation:
| Network | What its docs say |
|---|---|
| Link data updates on its own every 30 days; the Sharing Debugger forces a fresh scrape; images are cached by URL | |
| Post Inspector refreshes a URL, but only for new posts; existing posts keep their preview | |
| Slack | Unfurl responses are cached for around 30 minutes |
| X | The validator no longer previews; X suggests pasting the link into the post composer |
Two of those rules carry business weight. Meta says a link's title can change only until it has 50 interactions such as likes, comments and shares. And on Facebook and LinkedIn alike, a refresh fixes future shares, not posts already up. If the launch post takes off with the wrong title or a blank image, that version is the one people keep seeing.
What a preview check catches
A card is assembled from a handful of meta tags. When one is missing, the network guesses, usually with the page title and whatever image it finds first. A preview check shows the guess before your audience does.
The seogeoaeo.ai checker reads every og: and twitter: tag, shows which tag fed each part of the card and draws an approximate version of it. Then it flags the problems that cost clicks:
- no og:image, or one at a relative or http address
- a share picture that is too small, too heavy, the wrong format or the wrong shape for LinkedIn, Facebook or X
- an og:url that disagrees with the page's canonical address
- a title over 90 characters or a description over 200, which most cards cut short
- no twitter:card, which can leave X showing a small thumbnail card instead of the wide image
Who owns the fix
Most fixes are a template change, not a design project. The tags live in the page head, so whoever owns the CMS theme or the app layout owns them. Three cases need an engineer:
- Tags added by JavaScript. Preview crawlers read the raw HTML, and X says its crawler cannot run scripts. A single-page app may need server rendering for the tags to appear.
- A firewall or bot rule. If the image loads for you but not for crawlers, a security setting may be turning them away. LinkedIn's help lists this as a reason images fail to appear.
- Two plugins writing the same tags. Pick one and switch the other off.
The picture belongs to whoever makes the launch graphics. One 1200 by 630 file per page clears the published minimums for Facebook and LinkedIn, and X trims it slightly to fit its 2:1 card, so keep the logo and headline near the middle.
A launch-day routine
- Publish the page and run the seogeoaeo.ai check on the live URL.
- Fix what it flags and run it again.
- Paste the URL into Meta's Sharing Debugger and LinkedIn's Post Inspector, both free, so their caches hold the corrected card.
- Start a draft post on X, paste the link, look at the card, then delete the draft.
- Share.
A check costs 5 credits on seogeoaeo.ai. One honest limit: while the page sits on localhost or behind a staging password, no hosted tool can fetch it, the networks' own debuggers included. Read the tags with view-source until the page is public, then run the full check.