How to Test Open Graph Tags (and Debug Facebook and LinkedIn Previews)

Testing Open Graph tags is easier when you separate three questions: are the right tags in the HTML, can the image be fetched, and what does a particular platform show? Different tools answer different questions, and no single tool answers all three for every platform.

1. Check the HTML your server delivers

1. Open the page and use view-source (not the browser's Elements panel, which shows the page after JavaScript has run).
2. Search for og: and confirm og:title, og:type, og:image, og:url and og:description are present once each.
3. Check that the values belong to this page and contain no template placeholders.

An analyzer automates this and goes further. The Open Graph & Social Preview Analyzer fetches the page, lists every tag including duplicates, explains missing or inconsistent ones, and shows preview approximations with the source of each value. It reads the delivered HTML and does not execute JavaScript, which matches what most social crawlers see.

2. Check the image

• Open the og:image URL in a private window. It should load without logging in.
• Confirm it is a PNG or JPEG of reasonable size (see Open Graph image size).
• Check the HTTP status and Content-Type, and whether the URL redirects.

3. Use the platform's own tools

Only a platform can tell you what its crawler read and what its cache holds. The common ones are:

• Facebook's Sharing Debugger shows what Facebook's crawler found at a URL, any warnings, and offers a way to scrape the URL again.
• LinkedIn's Post Inspector fetches a URL, shows the preview LinkedIn would build, and refreshes LinkedIn's stored copy.
• For X, tooling for previewing cards has changed over time. Check X's current documentation for what is available, and test by sharing the link where you can do so safely.

These tools and their behavior change, so follow each platform's current documentation instead of fixed instructions. They are also the authority on that platform: if the analyzer and a platform disagree, the platform's result is the one your readers will see.

Debugging Facebook previews

• Make sure the URL you test is exactly the URL people share, including http versus https and any redirects.
• Read the warnings the debugger shows, such as missing properties or an inaccessible image.
• After fixing the page, use its scrape-again option, and use a new image file name if the old image persists.

Debugging LinkedIn previews

• Inspect the exact shared URL and read the title, image and domain it shows.
• LinkedIn commonly shows the title, image and domain; do not expect a long description.
• Inspect again after changes to refresh its stored copy.

A repeatable routine