Link Preview Checker
See exactly how your links appear when shared on social media and messaging apps
What are link previews?
Link previews (also called "unfurling") are the rich cards that appear when you share a URL on social media or messaging platforms. They typically show a title, description, image, and the domain name — giving your audience a preview of what they'll find when they click.
These previews are generated from Open Graph meta tags and Twitter Card tags in your page's HTML. When someone shares your URL, the platform's crawler fetches your page, reads the meta tags, and renders a preview card. If the tags are missing or misconfigured, the preview will be blank, broken, or show incorrect information.
Link previews have a massive impact on engagement. Research shows that links with rich previews get 5x more clicks than plain text URLs. A compelling preview image and description act as a mini-advertisement for your content, convincing people to click through. This makes it critical to verify your previews work correctly before sharing important links — whether it's a product launch, blog post, or marketing campaign.
link preview size requirements by platform
| Platform | Recommended Size | Aspect Ratio |
|---|---|---|
| Twitter / X | 1200 x 628 px | 1.91:1 |
| 1200 x 630 px | 1.91:1 | |
| 1200 x 627 px | 1.91:1 | |
| 400 x 400 px | 1:1 (square crop) | |
| Slack | 500 x 250 px | 2:1 |
| Discord | 400 x 200 px | 2:1 |
| 600 x 900 px | 2:3 (portrait) | |
| Telegram | 1200 x 628 px | 1.91:1 |
Common link preview issues and how to fix them
1. No preview image appears
The og:image tag is missing or the image URL is broken. Ensure the URL is absolute, publicly accessible, and the image file exists.
<meta property="og:image" content="https://example.com/preview.jpg" /> <meta property="og:image:width" content="1200" /> <meta property="og:image:height" content="630" />
2. Preview shows wrong title or description
Check that og:title and og:description are set correctly. If they're missing, platforms fall back to the <title> tag and <meta name="description">, which may not be optimized for social sharing.
3. Preview works on some platforms but not others
Twitter requires specific twitter:card tags. WhatsApp is stricter about image sizes. Test across all platforms using the checker above to identify platform-specific issues.
4. Preview shows stale/cached content
Platforms cache previews. After updating your OG tags, use Facebook's Sharing Debugger or Twitter's Card Validator to force a refresh. For other platforms, changing the og:image URL (even adding a query parameter) forces a re-fetch.
Frequently Asked Questions
Why does my link preview look different on each platform?▾
Each platform has its own rendering engine, image cropping rules, and character limits. Twitter uses a 1.91:1 aspect ratio, WhatsApp crops to a square, and Pinterest prefers tall portrait images. That's why checking previews across all platforms before sharing is essential.
How do I fix a broken link preview?▾
First, check that your page has og:title, og:description, and og:image tags with absolute HTTPS URLs. Then verify the og:image URL is publicly accessible (not behind auth or blocked by robots.txt). Finally, clear the platform's cache — Facebook has a Sharing Debugger, Twitter has a Card Validator.
Why is my link preview showing old content?▾
Social platforms cache link previews aggressively. Facebook caches for ~24 hours, LinkedIn for ~7 days, and Slack until the workspace cache clears. To force an update, use each platform's cache-clearing tool or add a cache-busting query parameter to your og:image URL.
Do link previews work with JavaScript-rendered pages?▾
Most social media crawlers do NOT execute JavaScript. If your OG tags are rendered client-side (e.g., in a React useEffect), they won't be picked up. OG tags must be in the initial HTML response. Use server-side rendering (SSR) or static site generation (SSG) to ensure tags are present in the HTML.
How do I test link previews without posting publicly?▾
Use Unfurli to preview your links across all 9 platforms without sharing anything publicly. For platform-specific testing, Facebook offers the Sharing Debugger, Twitter has the Card Validator, and LinkedIn has the Post Inspector — all free to use.
Can I customize the link preview for each platform?▾
Yes. Set default previews with og: tags, then override specifically for Twitter using twitter: tags (twitter:title, twitter:description, twitter:image). Other platforms like Facebook and LinkedIn will use the OG tags. There's no way to set platform-specific previews for WhatsApp, Slack, or Discord — they all use OG tags.