ExifTool is a platform-independent, open-source, free, and free-of-charge program that allows you to edit, read, and write metadata in a wide variety of files. The ExifTool is frequently integrated into digital workflows and supports many types of metadata and manufacturer-specific metadata formats for many digital cameras. This tool uses its own open metadata format. Meta information from many sources is bundled with any file type as binary or textual information. It may consist of a single file that wraps existing data, or it may be a sidecar file that contains, for example, Exif or XMP metadata.
Since version 12.23, ExifTool supports reading JPEG XL metadata. ExifTool shows you the file size, image width, image height, image dimensions and number of Megapixels.