Online Tool Store
Social Preview Checker
Paste a page's HTML to preview Facebook, LinkedIn, X, and Google cards, verify og:image loads at the right size, and catch missing tags before you deploy.
This works right here on your device — nothing gets sent out.
Example shown — replace it with your own page's "View source" HTML (right-click a page → View Page Source → copy → paste here).
How it works
- Open the page you want to check, right-click it, and choose "View Page Source".
- Copy the full HTML and paste it into the box above.
-
The tool reads the page's Open Graph (
og:*) and Twitter Card (twitter:*) meta tags, renders how each will look when shared, and checks every tag for missing values or lengths that platforms tend to truncate. -
It also renders a Google Search result preview from the
<title>and meta description, and loads theog:imageitself to confirm it's reachable and check its real pixel dimensions against Facebook's recommended size.
How the previews are built
Social platforms don't render your page when a link is shared — they read a fixed set of
meta tags out of the raw HTML instead. Facebook and LinkedIn read Open Graph tags directly;
X reads its own twitter:* tags first, and falls back to the matching Open
Graph tag whenever a twitter:* tag is missing:
twitter:title → og:title → <title>
That's the same fallback chain this tool uses to fill in the X preview when a page only defines Open Graph tags.
FAQ
Does my HTML or the page get sent anywhere?
No. The HTML you paste is parsed with your browser's built-in DOMParser, entirely on your device — nothing is uploaded or logged. If a tag references an image URL, your browser requests that image directly from wherever it's hosted, the same way any browser tab would.
Why do I need to paste HTML instead of just a URL?
This site has no backend — every tool runs entirely in your browser, and a browser can't fetch another site's raw HTML across origins the way a server could (that's the same-origin policy). Pasting the page's "View source" HTML sidesteps that: open the page, right-click → View Page Source, copy everything, and paste it here.
The preview looks different from what actually shows on Facebook or X.
Each platform has its own crawler and cache, and some (X included) only trust these tags from a page it has already crawled — a live page can look different here than on the platform until that platform re-crawls it. Treat this preview as what the tags say to render, not a guaranteed pixel-for-pixel match.
Why is my og:image not showing?
og:image (and twitter:image) needs to be a full, absolute URL starting with http:// or https:// — a relative path like /og/image.png is not enough for most platforms to resolve it. The checklist below flags this specifically.
What's the difference between the Facebook/LinkedIn card and the X card?
Facebook and LinkedIn read Open Graph (og:*) tags. X reads its own twitter:* tags first and falls back to Open Graph tags when a twitter:* tag is missing — that fallback is exactly what this tool simulates for the X preview.
What size should my og:image be?
Facebook recommends 1200×630 pixels (a 1.91:1 ratio) for the sharpest display. The minimum accepted size is 200×200 — below that, some platforms reject the image entirely — and anything under 600×315 will still show but noticeably smaller. The tag checklist loads your actual image and checks its real pixel dimensions against these thresholds.
Does this tool check if my og:image link actually works?
Yes. After you paste your HTML, the tool loads the og:image URL in your browser the same way a social platform's crawler would, and flags it if the image fails to load — a common cause of broken previews that a simple "is this a valid URL" check would miss.
How we compare
| Feature | Online Tool Store | metatags.io | opengraph.io | OpenGraphViewer |
|---|---|---|---|---|
| Works from pasted HTML — no live URL required | ✓ | ✗ | ✗ | ✗ |
| No sign-up required | ✓ | ✓ | Free tier (3 previews) | ✓ |
| Works on a page that isn't publicly live yet | ✓ | ✗ | ✗ | ✗ |
| Flags missing tags with a checklist | ✓ | Partial (char counters) | ✓ | ✓ |
| Google Search result preview | ✓ | ✓ | ✓ | ✗ |
| Loads og:image itself and checks its real pixel dimensions | ✓ | ✗ | ✗ | ✗ |
All three alternatives require your page to already be live at a public URL, since they fetch it themselves. Since Social Preview Checker works from pasted HTML, it also works on a page that's still local or behind a staging login — paste the source and see the checklist, including a real image-dimension check, before you ever deploy it.