Meta Tags for Social Sharing
When a URL is shared on many social networks the URL is checked for custom tags that control how the shared information will display on the platform.

The absence of these tags can adversely affect the way the information is presented.

Facebook

Essential tags below. Unless otherwise instructed Facebook defaults to the ‘website’ object type when a URL is shared. Other object types defined here, article type should be used for individual pages https://developers.facebook.com/docs/reference/opengraph/object-type/website/

Description should be between 2 and 4 sentences. Image should be at least 600x315 but larger than 1200x630 is recommended. URL should be without session variables, user identifying parameters, or counters.

<meta property="og:type" content="article">
<meta property="og:title" content="European Travel Destinations">
<meta property="og:description" content="Offering tour packages for individuals or groups.">
<meta property="og:image" content="http://euro-travel-example.com/thumbnail.jpg">
<meta property="og:url" content="http://euro-travel-example.com/index.htm">

Recommended but not essential

<meta name="og:site_name" content="European Travel, Inc.">

Only needed if Facebook Insights are being used

<meta property="fb:app_id" content="your_app_id" />

Twitter

Essential tags below. If some are not present Twitter can use Facebook’s og tags instead. So title, description and image can be omitted if the equivalent og tags are present.Title is max 70 characters. Description is max 200 characters. Image should reflect the content of the page and not be generic like an author image or logo.

<meta name="twitter:title" content="European Travel Destinations ">
<meta name="twitter:description" content=" Offering tour packages for individuals or groups.">
<meta name="twitter:image" content=" http://euro-travel-example.com/thumbnail.jpg">
<meta name="twitter:card" content="summary_large_image">

Recommended but not essential

<meta name="twitter:image:alt" content="Alt text for image">

Only needed if Twitter Analytics are being used

<meta name="twitter:site" content="@website-username">

LinkedIn

Uses the same tags as Facebook.

<meta property="og:title" content="My Shared Article Title" />
<meta property="og:description" content="Description of shared article" />
<meta property="og:url" content="http://example.com/my_article.html" />
<meta property="og:image" content="http://example.com/foo.jpg" />

Validation

Both Facebook and Twitter provide services to check the quality of the information to be shared.