How to use this link preview checker
- Get the tags. Paste the page's HTML (View Source, or just the
<head>), try fetching the URL, or use the bookmarklet on the page itself. - Look at the previews. Google result, LinkedIn, Facebook, X (large and summary), Slack, Discord, iMessage and WhatsApp.
- Fix what the checks flag. Each problem says what to change.
- Copy and refresh. Click "Fix in generator", copy the snippet into your site, then re-scrape in LinkedIn Post Inspector and the Facebook Sharing Debugger.
What is Open Graph?
Open Graph is a small set of <meta> tags, started by Facebook in 2010, that tells apps what to show when someone shares your link: the title, a short description, an image and the URL. LinkedIn, Slack, Discord, iMessage, WhatsApp and most other apps read the same tags. X reads them too, but wants one extra tag, twitter:card, to decide which card to draw. Without these tags, apps guess from your page, and the guess is usually a random image or none at all.
Required Open Graph tags
| Tag | What it does | Example |
|---|---|---|
og:title | Headline on the card | How we cut check-in time in half |
og:description | One or two lines under it | What we changed at our last three events |
og:image | The picture. Absolute https URL. | https://example.com/share.png |
og:url | The canonical address of the page | https://example.com/blog/check-in |
og:type | Kind of page, usually website or article | article |
twitter:card | Which card X shows | summary_large_image |
<link rel="canonical"> | The one true URL, for search engines | https://example.com/blog/check-in |
Nice to have: og:site_name, og:image:width and og:image:height (Facebook can show the image on the very first share), og:image:alt, og:locale, and theme-color (Discord uses it for the embed bar).
OG image size 2026: every platform
Short answer: make it 1200 x 630 px, PNG or JPG, under 5 MB, with the important bits in the middle. That one image works everywhere below.
| Platform | Recommended | Minimum / limits | Notes |
|---|---|---|---|
| 1200 x 630 (1.91:1) | 200 x 200 min, 8 MB max | Under 600 x 315 shows as a small image | |
| 1200 x 627 (1.91:1) | 1200 x 627 stated minimum, 5 MB max | Under 401 px wide shows as a thumbnail | |
| X large card | 1200 x 630 or 1200 x 600 | 300 x 157 min, 4096 x 4096 max, under 5 MB | Shown at about 2:1 (1.91:1 is cropped a little); JPG, PNG, WEBP, GIF |
| X summary card | Square, e.g. 600 x 600 | 144 x 144 min, 4096 x 4096 max, under 5 MB | Small square thumbnail, cropped to 1:1 |
| Slack | 1200 x 630 | No published numbers | Reads Open Graph and X card tags |
| Discord | 1200 x 630 | No published numbers | Big image with summary_large_image, else a small thumbnail |
| iMessage | 1200 x 630 or larger | No published numbers | Shows the image large, with title and domain below |
| 1200 x 630 | No published numbers | Recommended: keep the file small (around 300 KB or less); big files often show no image |
Checked against Facebook, LinkedIn and X developer docs on October 21, 2026. "No published numbers" means the platform doesn't document a size; the recommendation is what works in practice.
Meta tag generator
Switch to Generate tags, fill in the fields and copy the snippet. It writes the title, description, canonical, Open Graph and X tags, and checks them as you type. You can share the filled-in form with a link, so a teammate or developer sees exactly what you mean.
FAQ
What size should an og:image be in 2026?
1200 x 630 pixels (1.91:1), as a PNG or JPG under 5 MB. That works everywhere: it meets LinkedIn's 1200 x 627 minimum, Facebook's 1200 x 630 recommendation, and X crops it only slightly for its large card. Keep text and logos away from the edges.
Why does my link show the old image or title after I changed it?
Every platform caches the preview the first time someone shares the link. Re-scrape the URL in LinkedIn Post Inspector and the Facebook Sharing Debugger. For Slack, X, Discord and WhatsApp there is no public refresh button, so wait for the cache to expire or share the URL with a harmless query string like ?v=2.
Why can't this tool fetch my page directly?
Browsers block a web page from reading another site's HTML unless that site allows it (CORS). Platform crawlers run on servers, so they don't have this limit. Paste the HTML instead, or use the bookmarklet, which reads the tags from the page you are on and opens them here.
Do I need both Open Graph and Twitter card tags?
You need Open Graph tags plus one twitter:card tag. X falls back to og:title, og:description and og:image, so twitter:title and twitter:image are optional. Without twitter:card, X may not show a card at all.
Can og:image be a relative URL?
No. Use a full absolute URL starting with https://. Crawlers often don't resolve relative paths, so /images/share.png can end up as no image at all.
How long should the title and description be?
Google cuts titles at about 600 pixels wide, roughly 50 to 60 characters, and descriptions after about two lines, roughly 150 to 160 characters. Social cards show even less, often one or two lines, so put the important words first.
Are these previews exact?
No. They are close lookalikes, not official renderings, and the platforms change their layouts often. Use them to catch problems fast, then confirm with each platform's own debugger before a big launch.
Does this tool send my HTML anywhere?
No. Parsing and previews happen in your browser. The only network requests are the ones you ask for: fetching the URL you type, and loading the og:image so its size can be measured.
Last updated October 2026.