Question 1

What is an Open Graph (OG) image?

Accepted Answer

It's the preview image that appears when your URL is shared on X, LinkedIn, Slack, Discord, iMessage, WhatsApp, and more. You set it with a single <meta property="og:image"> tag in the page head. The same tag is read by almost every platform.

Question 2

What size should an og:image be?

Accepted Answer

1200 × 630 pixels, a 1.91:1 aspect ratio. That is the size every major platform expects for a large preview card. Keep the file under about 5 MB and use PNG or JPG. Images smaller than 600 × 315 get shown as a small thumbnail instead of a full card.

Question 3

Do I need both Open Graph and Twitter Card tags?

Accepted Answer

Open Graph alone covers most platforms, including X, which falls back to og:image and og:title when Twitter-specific tags are missing. Adding twitter:card set to summary_large_image guarantees X renders the full-width image. twitter:title and twitter:image let you tailor the X preview specifically if you want to.

Question 4

Why does my preview look different on each platform?

Accepted Answer

Each platform crops, truncates, and styles previews its own way. X shows a large image with the domain overlaid, LinkedIn puts the title under the image with the domain in uppercase, and Slack unfurls a compact card with a colored accent bar. They also truncate titles and descriptions at different lengths, which is why this tool renders each one separately.

Question 5

I updated my og:image but the old one still shows. Why?

Accepted Answer

Platforms cache previews aggressively. X, Facebook, and LinkedIn each have their own debugger that lets you force a re-scrape of a URL. Until you do, or until the cache expires, the old image keeps showing even though your tag is correct.

Question 6

Does the og:image URL need to be absolute?

Accepted Answer

Yes. Crawlers fetch the image from outside your site, so a relative path like /og.png will not resolve. Always use a full, absolute https URL such as https://yoursite.com/og.png.

Question 7

What does twitter:card summary_large_image do?

Accepted Answer

It tells X to render a large, full-width image card instead of the small square summary thumbnail. For most marketing and content pages, summary_large_image is what you want because it gives your image the most space in the feed.

Question 8

Is this validator free?

Accepted Answer

Yes. Paste any public URL and get an instant report of its Open Graph and Twitter Card tags, a faithful preview per platform, and specific fixes. No signup, no card, no limit worth worrying about.

Open Graph Image Validator

What makes a good OG image

1200 × 630, every time

Readable at a glance

A real image, not a logo

Tags that actually match

Open Graph, explained