A shared link needs enough context
A page may be clear when somebody is already on the website but vague when it appears in a message or social feed. Open Graph tags give a sharing crawler a title, description, page URL, image URL, and site name. The Open Graph Preview puts those fields together so you can check whether the card identifies the destination. It also creates the corresponding meta tags for the document head.
Write for somebody outside the website
Use a title that still makes sense without the navigation or page heading around it. The description should add a short explanation, not repeat the title word for word. Enter the canonical public URL rather than a staging address. For the image field, use an absolute HTTPS URL that a crawler can request without signing in. The tool also shows the hostname from the page URL, which can expose a copied development domain before publication.
What the image area currently does
The preview displays the image URL as a reference. It does not download, proxy, or validate the image. This is deliberate because accepting arbitrary URLs would require another protected server fetch. Check the image directly in your deployment and confirm that it returns a supported image response. A landscape image around 1200 by 630 pixels is a common starting point, but each platform decides how it crops and displays that file.
Why the preview is approximate
There is no single universal social card. Platforms use their own type sizes, spacing, image ratios, and fallback rules. They may shorten a description or ignore it. They can also cache an older version after the page changes. The neutral preview checks the relationship between your fields. It does not copy a specific network interface or promise that a final card will match it. Keep important subjects away from image edges so different crops remain usable.
Publish, inspect, and refresh
Copy the tags and place them in the page head through HTML or your framework metadata system. Then inspect the public HTML response to make sure the new values are present. Web Doctor can show the Open Graph fields it reads from that response. If one platform still shows old content, use its official sharing debugger or cache refresh tool when available. Changing the draft in this preview cannot clear a third-party cache.
What the tool does not check
The tool does not upload an image, test image file size, verify access permissions, or contact a social platform. It does not know whether a network will choose Open Graph fields, another metadata format, or content from the page. Use it to prepare and review the tags, then confirm the published result with the systems that will read them.