Open Graph
Open Graph is the tag protocol, originally created by Facebook, that controls how a URL appears when it is shared on social platforms and in messaging apps. It sets the title, description and preview image, and applies well beyond Facebook itself.
Why it matters for your rankings
Open Graph tags decide whether a shared link looks deliberate or broken. Without them platforms guess, often picking a logo fragment or the first stray image on the page.
The reach is wider than most people expect. Slack, WhatsApp, LinkedIn, Discord and iMessage all read these tags, so an internal link shared in a colleague's Slack channel is rendered by the same markup as a public post. Since share previews directly affect click-through, this is cheap conversion work rather than SEO. The recurring failure is caching: platforms store the first preview they fetch, so fixing the tags after a launch requires forcing a re-scrape rather than waiting.
How to check it on your site
Check the four core tags
og:title, og:description, og:image and og:url should be present on every important page.
Validate the preview
Use Facebook's Sharing Debugger and LinkedIn's Post Inspector to see the rendered card and force a fresh scrape.
Size images correctly
1200 by 630 pixels is the safe standard. Undersized images render as small thumbnails or get dropped.
Add Twitter card tags
twitter:card and related tags give explicit control on X rather than relying on Open Graph fallbacks.