Whether you want to add images on your website or email photos from your most recent party to all your friends, reducing the size of your JPEG images is often advisable. Very large images take a while to load and may not display at all for users on slow connections; an email containing several large images may not even be sent at all. You can make several changes to a JPEG image to reduce its size.
Launch your chosen image editing program and open the image you want to modify.
Crop the image with your chosen program's cropping tool to focus on important details and remove unnecessary ones. For example, if the focus of the image is a person, you can remove most of the background and still maintain the original image's meaning.
Resize the image to smaller dimensions. For example, if your image is 1000 by 2000 pixels, reducing it to 500 by 1000 or even 250 by 500 pixels will drastically reduce the file size while still preserving the important details. Depending on your chosen program, the option to resize an image may be called "Image Size," "Resize" or similar; consult your program's help files or manual for further information.
Reduce the image's quality. This process is usually performed during saving; most image editing programs will have a quality slider that allows you to easily choose what quality your image should be.
Always save your modified image with a different name than the original. This way, if you want to perform different changes to the same image in the future, you will be able to work from the high-quality original.
Reducing the quality of a JPEG image too much can blur the image and cause the loss of important details.