Open Graph & Twitter Card Checker
Check a page’s social meta tags and preview its share card.
How do I check my Open Graph and Twitter Card tags before sharing a link?
Paste the page's HTML source (or try its URL) into Docuboxer's Open Graph and Twitter Card checker, and it instantly scans for the 13 tags that Facebook, LinkedIn, Slack, WhatsApp and X actually read: title, meta description, canonical, every og:* property and every twitter:* tag. Each one is flagged as present, recommended-but-missing, or critical-and-missing, and the tool also catches the mistakes that quietly break share previews — a relative og:image URL instead of an absolute one, an og:url that doesn't match the canonical, or an invalid twitter:card value. A live preview shows exactly how the share card will render, with image, domain, title and description, so you're not guessing. Everything runs client-side against the HTML you paste or fetch yourself; nothing is uploaded or stored on a server. It's free, requires no signup, and works on pages that aren't live yet, since you control the HTML you feed it.
How to use Open Graph & Twitter Card Checker
- Open the page you want to check, right-click and choose “View Page Source” (or press Ctrl+U on Windows/Linux, Cmd+Option+U on Mac).
- Select all and copy the full HTML, then paste it into the “Paste HTML” tab — the check runs automatically as soon as you paste.
- Read the results table: each tag shows a checkmark if it's present, a warning triangle if a recommended one is missing, or an X if a critical one is missing.
- Fix whatever the warnings flag — a non-absolute image URL, an og:url that doesn't match canonical, an invalid twitter:card, or a title/description that runs too long.
- Compare the rendered card preview against what you expect, and download the .txt report if you need to hand it off to a teammate or client.
Common use cases
Sanity-check a campaign landing page before spending budget
Confirm the link you're about to run in paid ads or an email blast will actually show the right image and headline when shared, instead of finding out after the budget is already spent.
Debug why a link preview shows no image in Slack or WhatsApp
Catch that og:image points to a relative path like /img/social.png instead of a full https:// URL — the single most common reason share previews come back blank.
Audit tags a CMS or theme generated for you
Review what WordPress, Shopify, or a headless CMS auto-generated for Open Graph — templates often duplicate tags or leave og:url pointing at a stale version of the page.
Verify a domain migration didn't break share cards
Check that og:url and canonical still agree after moving to HTTPS or a new domain, so links shared before the migration keep resolving to a working preview.
Pre-launch checklist across key pages
Run every important page through the checker before a product launch to confirm title, description and og:image are all well-formed, without relying on memory to catch it.
Frequently asked questions
Why won't the image load when I check a URL directly?
Most sites block cross-origin fetch requests to their own HTML via CORS — that's a web platform limit, not something this tool imposes. Switch to the “Paste HTML” tab: open the page, copy its full source, and paste it there instead. The check runs exactly the same way.
What's the difference between og:image and twitter:image?
og:image is read by Facebook, LinkedIn, WhatsApp and most platforms following the Open Graph standard. twitter:image is X/Twitter-specific — if you skip it, X typically falls back to og:image, so you only need to set it separately if you want a different image on X.
Do I need twitter:card for a good preview on X?
It's not strictly required, but without it X has to guess the card type from whatever Open Graph tags are available, which is less predictable. Declaring summary_large_image explicitly gives you control over the image size shown.
Why does og:url need to match the canonical tag?
When they diverge, sharing signals like likes and shares can end up split across two different URLs for the same page instead of consolidating on one. Keeping them identical avoids that fragmentation.
Does the checker store or send the HTML I paste anywhere?
No. Parsing runs entirely in your browser using DOMParser — the HTML you paste never leaves your machine or touches a Docuboxer server.
What happens if a tag is duplicated in the HTML?
The checker uses the first occurrence in document order, the same way real Facebook and Twitter crawlers behave — so if og:title shows up twice, you'll see exactly which one actually gets used.