Open Graph Checker & Link Preview

What is an Open Graph checker and what does this one test?

An Open Graph checker downloads a page the way social networks do. It then shows the card people see when they share the link: title, description and image. WhatsApp, Facebook, LinkedIn and X all read the Open Graph tags in your page head. When a tag is missing, or the crawler cannot reach the page, the card breaks. It shows no image, the wrong headline or nothing at all.

This tool handles four jobs for one address.

• Preview: It draws eight platform cards close to their real layout, without brand logos.
• Audit: Over 25 checks cover the tags, the share image, crawler access and robots.txt.
• Edit: You change the title, description and image and see every card update instantly.
• Fix: You get a ready tag block with your page values, plus the steps to refresh each cache.

In my SEO consulting projects I run this check before any new page goes live. Once a campaign link lands in group chats with the wrong image, you cannot take it back.

Which Open Graph tags build a link preview?

The card rests on the Open Graph protocol. It requires four properties on every page: og:title, og:type, og:image and og:url. In practice, these tags shape the card.

• Title (og:title): Meta recommends leaving out branding such as your site name.
• Description (og:description): Meta suggests a short summary of 2 to 4 sentences.
• Image (og:image): Use an absolute URL that starts with https://.
• Address (og:url): Facebook counts likes and shares at this URL. So keep it identical to your canonical.
• Extras (og:site_name, og:type, og:locale): Site name, content type and language. Without og:locale the default is en_US.

X checks its own tags first: twitter:card, twitter:title, twitter:description and twitter:image. If they are missing, X falls back to the Open Graph values. So you do not need a separate X title. However, twitter:card has no Open Graph fallback; without it X can show a small summary card at best.

Duplicate tags cause surprisingly many support tickets. Open Graph takes the first tag in a conflict, while X uses the last twitter:card. When a theme and an SEO plugin both print tags, each platform may end up with a different card. The meta tag generator helps you produce all of them from one place.

What size should a share image be?

For one image that works everywhere, I prepare a 1200×630 pixel JPG or PNG at a 1.91:1 ratio. That size meets Meta's recommendation and clears LinkedIn's 1200×627 minimum. The X large card uses a 2:1 ratio, so cropping at the edges stays minimal.

Here are the official numbers.

• Meta rejects images under 200×200 and shows anything under 600×315 small. It accepts files up to 8 MB.
• LinkedIn allows up to 5 MB. However, images narrower than 401 pixels turn into thumbnails.
• X needs images under 5 MB. It supports JPG, PNG, WEBP and GIF, but not SVG. For an animated GIF, only the first frame appears.

Next to the image itself, add og:image:width and og:image:height. According to Meta, these two tags let the crawler render the image right away. Without them, the first share often shows no image. The tool compares these values with the real file and flags any mismatch.

Finally, keep text and logos in the center, because square and vertical layouts crop the edges. To bring an image to 1200×630, use the image resizer; the file never leaves your browser.

Why is the link preview not showing on WhatsApp?

WhatsApp publishes no official image size or character limit for previews. So I check the usual causes in this order.

1. Missing or unreachable og:image. If the image returns 404 or a firewall stops the download, the card shows text only.
2. Slow page or error. The preview forms in a short window before sending. If the page lags, WhatsApp may leave a plain link.
3. Not the first link. Meta's WhatsApp Cloud API documentation says only the first URL in a message gets a preview.
4. Previews switched off. WhatsApp has a setting under Settings, Privacy, Advanced that disables link previews. With it on, your messages carry no card; the recipient's setting does not change your message.

A large landscape image gives a wide card. A small or nearly square one gives a thumbnail. The WhatsApp preview in this tool copies that behavior. Need a link that opens a chat in one tap? The WhatsApp link generator adds your page URL to the message. The preview then comes from that page's tags.

Can social crawlers reach your page?

This is the costliest problem. The page looks perfect in a browser, yet every share goes out bare. That is why the tool requests the page twice: first with its own identity, then as facebookexternalhit. For example, a 403 or 5xx on the second request points to a firewall, bot protection or CDN rule that blocks social crawlers.

One honest caveat: some security systems accept this identity only from Meta's real IP addresses. In that setup the tool sees a block while real shares still work. To be sure, test the same URL in Meta's Sharing Debugger.

The Open Graph checker also looks at three more points.

• Robots rules: X's documentation says Twitterbot follows robots.txt. A blocked page gets no card, and a blocked image gets no thumbnail.
• The first 1 MB: Meta wants Open Graph properties within the first 1 MB of the HTML. Long inline scripts can push tags past that point.
• Tags outside the head: Crawlers may miss tags that end up in the body.

The tool does not run JavaScript. Sites that add tags with JavaScript often show crawlers an empty head as well. So write the tags into the HTML your server sends. For overall technical health, also run the SEO checker.

How do you refresh a cached link preview?

You fixed the tags, yet WhatsApp still shows the old image? The cache is the likely culprit. Platforms do not download your page on every share; they keep what they read first for a while. Messages you already sent never change either, so a refresh only affects new shares.

• Facebook and Messenger: enter the URL in the Sharing Debugger and scrape again. Meta caches images by URL, so give a replaced image a new file name.
• LinkedIn: Post Inspector reads the URL again and updates the preview for new posts.
• X: according to its documentation, card data stays cached for 7 days after a post. If you cannot wait, add a harmless parameter such as ?v=2 and share it as a new address.
• WhatsApp: there is no official refresh tool; the same parameter trick works for new messages.
• Telegram: send the URL to Telegram's @WebpageBot account and the preview rebuilds.

The Code & cache tab gives you these links ready to click and copies the parameter address in one go. On Facebook, however, do not rely on the parameter trick, since Facebook counts shares at the og:url address.

What should you fix first after running the Open Graph checker?

Even a technically perfect card can fail to earn clicks. People scrolling a feed decide on the image and a one line headline. That differs from a search result, so I treat card copy separately and fix things in this order.

• Access first. A page that crawlers cannot reach makes every other fix pointless.
• Next, the image. Aim for 1200×630, under 5 MB, JPG or PNG, with width and height tags.
• After that, the headline. Write og:title as a 40 to 60 character promise to the reader. X's 70 character limit then never bites.
• Then the description. Put the question in the first sentence and the answer's location in the second. LinkedIn often hides the description, so the headline carries the message.
• Finally, one card per page. The same logo image on every page makes all shares look alike.

Search titles follow their own rules, covered in my guide on how to write a meta title and description. For turning shares into site traffic, read how to drive website traffic from social media. You can test your Google look in the SERP preview.