Test Link Previews on Facebook, LinkedIn & X

Link previews are the thumbnail image, title, and description that appear when you share a URL on social media. Testing them before you post ensures your content looks professional and clickable. This guide walks you through checking and fixing previews on Facebook, LinkedIn, and X (formerly Twitter) using their built-in debugging tools.

What You’ll Need

The exact URL of the page you want to share
Access to the page’s HTML source (or ability to edit it) if you need to fix missing or wrong preview data
A Facebook, LinkedIn, and/or X account (you can use the tools without posting, but an account helps when sharing)

Step-by-Step

Check the page’s current meta tags. Open the URL in a browser, right-click and select “View Page Source” (or press Ctrl+U on Windows / Cmd+U on Mac). Look for <meta property="og:title">, <meta property="og:description">, and <meta property="og:image">. These Open Graph tags control how most platforms display your link. If they’re missing, the platform will guess from the page content, often with poor results.
Test on Facebook with the Sharing Debugger. Go to developers.facebook.com/tools/debug/. Paste your URL into the input field and click “Debug”. The tool shows you exactly what Facebook sees: the title, description, image, and any warnings or errors. If you’ve recently updated the page, click “Scrape Again” to refresh Facebook’s cached data.
Test on LinkedIn with the Post Inspector. Visit www.linkedin.com/post-inspector/. Enter your URL and click “Inspect”. LinkedIn will display the preview as it would appear in a post, along with the raw meta data it detected. Note that LinkedIn can be slow to update its cache, so if you make changes, wait a few minutes and re-inspect.
Test on X (Twitter) with the Card Validator. Go to cards-dev.twitter.com/validator. Paste your URL and click “Preview Card”. X shows you the card type (summary, summary_large_image, etc.) and the exact image, title, and description that will appear. If you’ve changed anything, click “Refresh Preview” to clear the cached version.
Check the image requirements. Each platform has different ideal image sizes. For Facebook and LinkedIn, aim for 1200×630 pixels. For X, use 1200×675 pixels (or 800×418 for summary cards). Ensure the image is under 5MB and in JPG or PNG format. If your image is too small or the wrong aspect ratio, the platform may crop it or not show it at all.
Verify the URL is accessible. The debugging tools will fail if your page is behind a login, blocks bots, or has a robots.txt that disallows crawling. Make sure the URL is publicly accessible and returns a 200 status code. You can check this with a simple curl command or an online HTTP status checker.
Fix issues and re-test. If the preview is wrong, edit your page’s meta tags. Add or correct the og:title, og:description, and og:image tags in the <head> section. Also add a twitter:card tag (e.g., summary_large_image) for X. After saving, return to each debugger and scrape/inspect again to confirm the fix.

Common Mistakes

Using the wrong image URL. The og:image must be an absolute URL (starting with https://), not a relative path like /images/thumb.jpg.
Forgetting to update the cache. Platforms cache previews aggressively. Even after fixing your meta tags, the old preview may persist for hours or days unless you use the debugger’s “Scrape Again” or “Refresh Preview” button.
Ignoring the description length. Facebook and LinkedIn truncate descriptions around 200 characters, X around 100. Keep your og:description under 200 characters to avoid cut-offs.
Missing the og:type tag. While not always required, specifying og:type="website" (or “article” for blog posts) helps platforms understand the content and sometimes improves the preview layout.
Testing only one platform. Each platform uses slightly different logic. A preview that looks great on Facebook might be broken on X. Always test on all three.

Tips

Use a consistent image. Choose a single, high-quality image that represents your content well. Avoid using your logo if the article has a relevant photo—logos are often ignored or cropped poorly.
Set a default image. If your page doesn’t have an image, add a generic fallback og:image so the preview isn’t blank. Many platforms will refuse to show a preview without an image.
Test on mobile. The debuggers show desktop previews, but mobile apps may render differently. After posting, check how the preview looks on your phone’s app.
Use a URL shortener for testing. If you’re testing a long URL with many parameters, shorten it first. Some platforms may have issues with complex URLs, and shorteners also help you track clicks.
Keep your meta tags in sync. Ensure your og: tags match your twitter: tags (or at least the title and image) to avoid inconsistencies across platforms.

Troubleshooting

Preview shows an old image or title. This is almost always a caching issue. Go back to the debugger and click “Scrape Again” (Facebook) or “Refresh Preview” (X). For LinkedIn, wait 5–10 minutes and re-inspect. If it still shows old data, try adding a query string to the URL (e.g., ?v=2) to force a fresh fetch—but remember to use that new URL when sharing.
No preview appears at all. Check that your page has the required meta tags. If they’re missing, add them. Also verify that your server isn’t blocking the platform’s crawler. Check your robots.txt file to ensure it doesn’t disallow facebookexternalhit, LinkedInBot, or Twitterbot.
The image doesn’t show. Confirm the image URL is absolute and accessible. Open the image URL directly in a browser—if it 404s, the image is broken. Also check the image dimensions; if it’s too small (under 200×200), platforms may ignore it.
The title or description is wrong. Your page might have multiple title tags or conflicting Open Graph tags. Use the debugger to see which tags are being picked up. Remove any duplicate or conflicting tags in your HTML.
The preview works on Facebook but not on X. X requires specific twitter: tags (or it falls back to og:). If you only have og: tags, X should still work, but if it doesn’t, add <meta name="twitter:card" content="summary_large_image"> and <meta name="twitter:title" content="...">.
Changes still don’t appear after scraping. Some platforms have a long cache TTL. As a last resort, share the URL with a fake query parameter (e.g., ?utm_source=test) to get a fresh preview. If that works, use that parameter in your actual posts.

Frequently Asked Questions

Do I need to test every URL I share?

Not every time, but it’s wise for important links like blog posts, product pages, or any URL you’ll share widely. A quick test takes less than a minute and prevents an embarrassing broken preview.

Can I test a preview without posting it?

Yes. All three debugging tools let you enter a URL and see the preview without actually publishing anything. You can also paste the link into a private message or a draft post to see the preview in the composer.

Why does my preview look different on mobile vs. desktop?

Mobile apps often use a slightly different rendering engine and may have different image size requirements. Always check on your phone’s app before finalizing a major post.

What is the ideal image size for link previews?

For Facebook and LinkedIn, use 1200×630 pixels. For X, use 1200×675 pixels for a large summary card. If your image is smaller, it may still work but could be cropped or blurred.

How long does it take for a preview to update after I fix it?

Facebook and X update almost immediately after you click “Scrape Again” or “Refresh Preview”. LinkedIn can take a few minutes to a few hours. If you’re in a hurry, use the query-string trick to get a fresh preview.

Can I test a preview for a page that requires login?

No. The debugging tools cannot access pages behind a login. You’ll need to make the page public temporarily or test a version without authentication.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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