miji.beA link preview is the card-style display that automatically appears when you share a URL on social media or messaging apps. It typically shows the page's title, a thumbnail image, and a brief description. The Twitter card that appears when you paste a URL in a tweet, or the image summary shown when sending a link on LINE, are examples of link previews.
Link previews pull their information from OGP (Open Graph Protocol) tags and Twitter Card tags embedded in the page's HTML. The og:title tag provides the title, og:description supplies the summary text, and og:image specifies the thumbnail. Without these tags properly configured, previews may not appear or may display unintended content.
The impact on click-through rates is significant. Links with proper thumbnail images tend to get more clicks than those without an image. The recommended og:image size is 1200x630 pixels, which displays optimally across major platforms.
The relationship between short URLs and link previews requires attention. When a short URL is shared, the social platform's crawler follows the redirect to the destination page and extracts OGP information from there. Most platforms handle redirects correctly, but long redirect chains or slow server responses can cause preview generation to fail.
Link preview caching is another consideration. Once generated, previews are cached by the social platform and won't immediately reflect OGP tag changes. Twitter's Card Validator and Facebook's Sharing Debugger can force cache refreshes.