Link Preview Checker

Link Preview Checker reads a page's Open Graph and X card tags on our server, measures og:image in your browser, and shows approximate previews for seven apps.

At a glance

Accepts: A page URL, or pasted HTML
Outputs: The preview tags found, image size and errors, and approximate unbranded preview cards for WhatsApp, LinkedIn, X, Facebook, Slack, Discord and iMessage
Where it runs: On our server
What leaves your device: In URL mode the URL is sent to our server, which downloads the page (not stored); pasted HTML is read in your browser and never sent
Limits: Cards are approximations of each app's layout; reads the HTML before JavaScript runs; first 2 MB of the page
Account: Not required - there is no sign-up
Price: Free, with no watermark and no usage cap
Made by: Visrut
Last updated: 14 October 2026

When you paste a link into a chat or a post, the app fetches the page and builds a card from its Open Graph tags (og:title, og:description, og:image) and, on X, its twitter:card tags. A missing image, a relative image URL or a tiny thumbnail turns that card into a bare link. This checker reads those tags the way the apps do, measures the image, flags what's wrong and shows approximate cards for seven apps.

How to use it

Enter the page URL and press Check preview. For a page that isn't live yet, or blocks our server, use Paste HTML.
Fix errors first: a missing or broken og:image matters most.
Already shared the link? Refresh the cached preview in Facebook's Sharing Debugger and LinkedIn's Post Inspector.

The tags that matter

og:image - a full https URL to an image of at least 1200 x 630 pixels (Facebook's image guidance) or 1200 x 627 (LinkedIn's), ratio 1.91:1. Checked 13 October 2026.
og:title and og:description - what the card says. Keep the point of the description early: cards show a line or two.
twitter:card - summary_large_image for a big image on X, summary for a small square one.
og:url - the page's canonical address, so shares of the same page with different tracking parameters count together.

Honest limits

The cards are approximate and unbranded; the real apps decide their own layouts and change them.
It reads the HTML before JavaScript runs, like the apps' crawlers.
Some apps (and some sites' firewalls) treat their own crawlers differently from ours, so a site that blocks us may still work for them, and the other way round.

Related SEO checks

Redirect Checker - follow every hop of a redirect chain
Sitemap Validator - check or build a sitemap.xml
Schema Markup Checker - test structured data for rich results
Domain Info - look up a domain's age and registrar

Frequently asked questions

Does this send the URL to your server?

In Check a URL mode, yes: browsers can't read another site's HTML, so the URL is sent to our server, which downloads the page and returns the tags it found. We don't store the URL or the page. The preview image is then loaded by your own browser. In Paste HTML mode nothing is sent to us - the tags are read in your browser.

Are these previews exactly what WhatsApp, LinkedIn or X will show?

No - they are approximate. Each app picks its own layout, crops images differently on phones and desktops, and changes its design without notice. The cards here show which title, description and image each one is likely to use, so you can catch a missing or wrong tag before you share.

I fixed my tags but the old preview still shows. Why?

The platforms cache previews. Facebook's Sharing Debugger and LinkedIn's Post Inspector fetch the page again and refresh their copy. Facebook also caches images by URL, so a changed image needs a new image URL. Other apps refresh on their own schedule.

What size should og:image be?

Facebook recommends at least 1200 x 630 pixels, as close to 1.91:1 as possible, under 8 MB and no smaller than 200 x 200. LinkedIn asks for at least 1200 x 627 at 1.91:1. One 1200 x 630 image suits both, and most other apps.

Why does my page fail with HTTP 403 or a timeout?

Some sites block requests from cloud servers like ours. Open the page, view its source (Ctrl+U, or Cmd+Option+U on a Mac), copy it and use Paste HTML instead.

My tags are added by JavaScript. Will they work?

Usually not. Link preview crawlers read the HTML your server sends and generally don't run JavaScript, so tags added later by a script are invisible to them. This checker reads the same server HTML, so if a tag is missing here it is probably missing for them too.