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Open Graph Debugger: Fix Broken Social Previews

October 16, 2026 · 5 min read · By the DollarWise team
Open Graph Debugger: Fix Broken Social Previews
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You share your article link. Instead of your beautiful featured image and clever headline, the preview shows… a grey box. Or last month’s image. Or no image at all. Broken social previews silently kill click-through rates — people don’t click links that look broken.

The fix is a combination of correct Open Graph tags and each platform’s debugger tool to clear stale caches. Start by generating proper tags with our free Open Graph tag generator, then use this guide to diagnose and fix whatever’s wrong.

How social previews actually work

When you paste a link into Facebook, X, LinkedIn, Discord, or Slack, the platform’s crawler fetches your page and looks for Open Graph meta tags in the <head>:

  • og:title — the headline shown in the preview
  • og:description — the summary text
  • og:image — the preview image
  • og:url — the canonical URL
  • og:type — usually “website” or “article”

The crawler then caches what it found — often for days or weeks. This cache is the source of most “broken preview” mysteries: you fixed the tags, but the platform is still showing what it scraped last Tuesday. Debuggers exist precisely to inspect this cache and force a re-scrape.

The essential Open Graph tags (get these right first)

Before debugging, make sure the tags themselves are correct. Every page you want shared needs at minimum:

<meta property="og:title" content="Your Page Title">
<meta property="og:description" content="A compelling 1-2 sentence summary.">
<meta property="og:image" content="https://yoursite.com/images/preview.jpg">
<meta property="og:url" content="https://yoursite.com/your-page/">
<meta property="og:type" content="article">

For X (Twitter), add: <meta name="twitter:card" content="summary_large_image"> — without it, X falls back to a small thumbnail.

Image rules that prevent 90% of problems:

  • Absolute URL (https://…), never relative paths — crawlers can’t resolve relative image URLs
  • 1200×630px dimensions for crisp display everywhere
  • Under 8MB file size (under 1MB is safer — some crawlers time out on huge images)
  • Publicly accessible — no hotlink protection, no login walls, no robots.txt blocks on the image

Generate a complete, correct tag set with our free Open Graph tag generator instead of hand-writing them.

Debugging platform by platform

Facebook / Instagram / Threads — Sharing Debugger. Enter your URL and click “Scrape Again.” It shows exactly what Facebook’s crawler sees: the fetched tags, the image, and any errors or warnings. The “Scrape Again” button busts the cache — this alone fixes most stale-preview issues. Common warnings: image too small, image inaccessible, missing og:title.

X (Twitter) — Card Validator. Paste the URL to preview the card and refresh X’s cache. X is picky about the twitter:card tag — summary_large_image gives you the big image layout; without it you get a tiny thumbnail regardless of your og:image.

LinkedIn — Post Inspector. LinkedIn caches aggressively (up to 7 days) and its inspector is the only reliable way to force a refresh. LinkedIn is also strict about image accessibility — if your server is slow or the image URL redirects, LinkedIn silently drops the image.

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Discord / Slack / WhatsApp. These have no public debugger — they cache the first scrape and offer no manual refresh. Your only lever is correct tags from the start, plus appending a cache-busting query parameter (?v=2) to the URL when sharing, which forces a fresh scrape of what the crawler sees as a “new” URL.

The most common preview failures (and fixes)

Wrong or old image. Cause: stale cache 90% of the time. Fix: re-scrape in the platform debugger. If it persists, verify og:image is an absolute HTTPS URL pointing to a publicly fetchable file.

No image at all. Causes: missing og:image tag, relative image URL, image blocked by robots.txt or hotlink protection, image too large (crawler timed out), or slow server response. Check each in order.

Wrong title/description. Stale cache again — or your CMS outputs different tags than you think (view page source to confirm what’s actually in the <head>). Dynamic sites sometimes serve crawlers different HTML; check with the debugger’s “view source” output.

Preview works on Facebook but not LinkedIn. Independent caches and different strictness. Debug each platform separately; LinkedIn especially dislikes redirect chains on image URLs.

Image looks blurry. Your og:image is smaller than 1200×630 or heavily compressed. Social platforms don’t upscale gracefully — serve the full recommended size.

Frequently asked questions

Usually a cached old preview or a missing og:image tag. Set a proper og:image (1200×630px, absolute HTTPS URL), then re-scrape the URL in the platform’s debugger to clear the cache. Facebook’s Sharing Debugger “Scrape Again” button fixes this in seconds.

Use Facebook’s Sharing Debugger: enter the URL, click “Scrape Again” to refresh the cache, and fix any missing og:title, og:description, or og:image tags it reports. Generate correct tags first with our free Open Graph tag generator.

What size should Open Graph images be?

1200×630 pixels is the universal recommendation — it displays crisply on Facebook, LinkedIn, Discord, and Slack. Keep the file under 8MB (ideally under 1MB) for reliable fetching, and always use an absolute HTTPS URL.

Why does my preview work on one platform but not another?

Each platform caches independently and has slightly different requirements. X needs twitter:card tags for large images, LinkedIn is strict about image accessibility and caches for up to 7 days, and Discord/Slack offer no manual cache refresh. Debug each platform with its own tool.

#seo#open-graph#social-media
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Written by the DollarWise team

We turn confusing money topics into plain-English guides for beginners. Every article is written to be actionable on day one — no jargon, no hype, no sales pitch.

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