The JPEG (Joint Photographic Experts Group) format preserves image quality. It can also compress the image file so it takes up less space, allowing it to be downloaded or transmitted quickly. The JPEG has thus become the most popular picture format on the Internet. If you want to download a JPEG to your hard drive from the Internet or transmit it via email to someone else, knowing its size can gauge how much space or time it will take.
Right-click on an image within a website to reveal the pop-up menu.
Choose "Properties" in Internet Explorer to display the "Properties" dialog box, or choose "View Image Info" in Mozilla Thunderbird to display the "Page Info" dialog box. Note that the actual command differs slightly in other browsers.
Click the "Media" icon in Thunderbird if it is not already selected. The center panel of both the "Explorer" and "Thunderbird" dialog boxes reveals the location of the picture, its type, file size and dimensions in pixels.
Open your favorite file manager if the JPEG is located on your hard drive. For example, to open Windows Explorer, click the "Start" button and then choose "All Programs" followed by "Accessories" and "Windows Explorer." The program window appears.
Navigate to the JPEG file that you wish to find the size of.
Right-click on the file name, and then choose "Properties" from the pop-up menu. The "Properties" dialog appears.
Click the "General" tab if it is not already selected. The center part of the dialog describes the size of the file.