This tool validates the opengraph tags in your web page. It checks for two types of tags: Facebook and X.
If a defined image has the dimensions 1200 x 630 it will appear in the results with a green background. If not, it will appear with a red background. A missing value will also appear with a red background.
Handy tip: To quickly check the opengraph tags of the web page you're currently viewing, use the following bookmarklet. Just drag the red button up to your bookmarks bar. Then click it while on any web page.