Kentico 11: How to get Width and Height from image?

Check the API examples at docs.kentico.com/...#Medialibraries-Mediafoldersandfiles

If you have the item GUID you'd do something like:

CMS.MediaLibrary.MediaFileInfo yourfile = CMS.MediaLibrary.MediaFileInfoProvider.GetMediaFileInfo(fileGuid, SiteContext.CurrentSiteName);

or if you just have the path: (you might need to remove the ~ or first /.)

CMS.MediaLibrary.MediaFileInfo yourfile = CMS.MediaLibrary.MediaFileInfoProvider.GetMediaFiles().Where("FilePath", yourMediaPath).FirstObject();

The media file itself has the following properties:

    var imgHeight = yourfile.FileImageHeight;
    var imgWidth = yourfile.FileImageWidth;