How Each Platform Reads Your Metadata

Every platform generates link previews differently. Here’s what each one reads and what happens when tags are missing.

Facebook / Meta

Reads: og:title, og:description, og:image, og:url, og:type

Facebook strictly follows the Open Graph protocol. It reads og:image for the preview image, falls back to the first image on the page if missing (unreliable). Images should be at least 1200x630px.

Cache: Aggressive. Use the Sharing Debugger to force a refresh after changing tags.

X / Twitter

Reads: twitter:card, twitter:title, twitter:description, twitter:image. Falls back to og:* equivalents.

The twitter:card tag controls the layout:

• summary — small square image beside the text
• summary_large_image — full-width image above the text

Without twitter:card, X uses summary by default. Most sites want summary_large_image.

Cache: Re-fetches periodically. The Card Validator forces a refresh.

LinkedIn

Reads: og:title, og:description, og:image, og:url

LinkedIn follows OG tags closely. It crops images to a 1.91:1 ratio (1200x628). Images smaller than 200x200 are ignored entirely.

Cache: Very aggressive. LinkedIn’s crawler caches for up to 7 days. The Post Inspector can trigger a re-scrape.

Discord

Reads: og:title, og:description, og:image, og:site_name, theme-color

Discord is unique — it uses <meta name="theme-color"> to color the left border of the embed. It also respects og:site_name for the small text above the title.

<meta name="theme-color" content="#5865F2">
<meta property="og:site_name" content="Your Site Name">

Cache: Re-fetches when you edit and re-paste a link in chat.

iMessage / Apple

Reads: og:title, og:description, og:image

Apple’s crawler is strict about HTTPS and valid SSL certificates. Self-signed certs or HTTP URLs won’t generate previews.

Images must be served from the same domain or a well-known CDN. Apple blocks images from unfamiliar origins.

Slack

Reads: og:title, og:description, og:image, twitter:card

Slack combines OG and Twitter card data. It uses twitter:card to decide the image layout (similar to X). Without it, images show as small thumbnails.

Common pattern

For maximum compatibility across all platforms:

<meta property="og:title" content="Your Title">
<meta property="og:description" content="Your description, 55-200 chars.">
<meta property="og:image" content="https://yoursite.com/og.png">
<meta property="og:image:width" content="1200">
<meta property="og:image:height" content="630">
<meta property="og:url" content="https://yoursite.com/page">
<meta property="og:type" content="website">
<meta name="twitter:card" content="summary_large_image">

This covers Facebook, X, LinkedIn, Discord, Slack, iMessage, and most other platforms that render link previews.