Free Open Graph checker: why your link preview is blank
A preview is generated at share time by a scraper that does not run JavaScript and gives up quickly. Almost every broken preview comes down to one of four causes.
By Sapun Lamichhane · Arcetis
A blank link preview is a peculiar kind of failure. Nothing is broken on your site, no error is logged, and the cost is entirely invisible: a link shared into a group chat or a social feed with no image, no title and nothing to click for.
What actually happens when someone shares a link
The platform sends a scraper to fetch your URL. That scraper does not execute JavaScript, does not wait long, and reads only the head of the document. It takes what it finds and gives up.
Every common cause of a broken preview follows directly from those three properties.
The four causes
- A relative og:image path. The specification requires an absolute URL, and a relative one is the single most common cause of a missing preview image.
- Tags added by client-side JavaScript. The scraper never runs it, so the tags do not exist as far as it is concerned. Framework-set meta tags are reliably visible to Google and reliably invisible here.
- An unreachable image — behind authentication, blocked by a firewall, or on a staging host that no longer resolves.
- An oversized or unusual file. Over about 5MB is commonly dropped without comment, as are less common formats.
The tags worth having
- 1og:title, og:description, og:url and og:image — the four that build the card.
- 2og:type, usually website or article.
- 3twitter:card set to summary_large_image, plus twitter:title and twitter:description.
- 4An image at 1200x630, absolute URL, under 5MB.
Caching, and why your fix seems not to have worked
Platforms cache previews aggressively. After fixing your tags, the old preview will keep appearing until the cache clears — which is why several platforms provide a debugger with a force-refresh. If you fix the tags and see no change, this is usually why, and re-editing the tags will not help.
What free means here
Our Open Graph checker is free, with no account needed for your first scan. It reports which tags are present, whether the image URL is absolute and reachable, and — the part most checkers miss — whether the tags exist in the server-rendered HTML, where a scraper will actually find them.