What are Open Graph tags?
Open Graph meta tags tell social platforms and messengers what to show when someone shares your link: the title, description, and preview image. Without them, platforms guess, and the guess is often an empty card or a random image. The twitter:card tag controls the same preview on X.
Image size and text length
Use a 1200×630 image (1.91:1); it works across Facebook, LinkedIn, Slack, and X's large card. Keep the title near 60 characters and the description near 110 so previews don't truncate mid-sentence. Always use absolute URLs for og:url and og:image.
FAQ
Where do I paste these tags?
Inside the <head> of your HTML page. In Next.js or another framework, use its metadata API instead and copy the values over; the generated HTML shows exactly which fields to fill.
Why doesn't my preview update after changing tags?
Platforms cache link previews. Re-scrape with each platform's debugger (Facebook Sharing Debugger, LinkedIn Post Inspector) or share the URL with a query string appended to bypass the cache.
Is anything uploaded?
No. The tags are generated entirely in your browser; the image URL is only loaded locally for the preview.