Meta tag and Open Graph generator

How to use the tool

To check a page that is already live, paste its URL and click “Fetch”. The tool reads its tags, fills in the fields and flags what is missing: an absent Open Graph tag, an image given as a relative address, a forgotten viewport tag. For a page you are still preparing, simply fill in the fields.

The checks and previews update as you type. Your browser loads the image to measure its width and height, which are added to the code. Once everything is green, copy the code and paste it into the <head> of the page, in place of the existing tags.

Who reads which tags?

A page’s tags are not all meant for the same readers. Google reads the title tag, the meta description, the robots tag and the viewport tag, whose presence tells it that the page is mobile-friendly. It ignores the keywords meta tag, which it lists among unsupported tags.¹

Facebook, LinkedIn, messaging apps and most social platforms read Open Graph tags, a public protocol.² X reads its own tags, which start with twitter:, and falls back on Open Graph tags when they are missing. A well-tagged page therefore carries all three families, without needlessly repeating what X can pick up on its own.

The essential Open Graph tags

The Open Graph protocol requires four on every page: og:title, the title of the content; og:type, its type; og:image, the image URL; og:url, the page’s canonical URL, which serves as its permanent ID. It also recommends og:description, a one or two sentence summary, og:site_name, the site name, and og:locale, the language. As soon as a page specifies an image, it should also provide og:image:alt, a description of what the image shows.²

Meta’s documentation for webmasters adds two useful details.³ Without og:type, Facebook treats the page as a website. And og:title should carry the title of the content without the site name, which og:site_name already displays: the tool flags it when it finds the site name in the share title.

What size should the share image be?

Each platform publishes its own requirements. Here are the ones the tool checks.

A 1,200 × 630 pixel image satisfies everyone: it matches the size Facebook recommends, exceeds LinkedIn’s minimum by three pixels in height, has 756,000 pixels for Discover, and X crops it slightly to bring it to 2:1. Keep the subject in the middle, since the edges can be cut depending on the platform.

X cards

The twitter:card tag chooses the shape of the card. With summary_large_image, the image spans the full width above the link; with summary, it becomes a small thumbnail next to the text. Without twitter:card, but with og:type, og:title and og:description, a small card may be shown: to get the large image, you must declare summary_large_image.⁶

X falls back on og:title, og:description, og:image and og:image:alt when the matching twitter: tags are missing. The tool’s code therefore sticks to twitter:card and, if you fill it in, twitter:site, the account the card is attributed to. X also asks for an image specific to the page rather than the site logo or an author photo used everywhere.⁶

Why the preview does not change after a fix

Platforms remember what they read the first time a link was shared. Meta caches images by their URL: to replace an image that has already been shared, publish the new one at a different URL, then ask its sharing debugger to read the page again. Meta also recommends declaring og:image:width and og:image:height: with these two tags, the image can be shown on the very first share, without waiting for the crawler to download it.⁴ That is why the tool measures the image and adds them to the code.

Open Graph and SEO

Open Graph tags do not appear in the list of meta tags Google says it supports for Search.¹ Their first job is sharing. Google Discover is the exception for the image: Google states that the og:image tag, like schema.org markup, can influence the thumbnail chosen, provided large images are allowed by max-image-preview:large.⁷ Schema.org markup itself belongs to structured data and rich results.

For the Google result itself, the title tag and the meta description are what count. Their pixel width and their preview on desktop and mobile can be checked with the title and meta description length checker.

Frequently asked questions