A JPG, or JPEG, is a photographic file type created by the Joint Photographic Experts Group. Many digital cameras save images as JPG files. Web page designers also use JPG files on many websites. If you have a JPG file on your computer or on your digital camera that you wish to enlarge so you can print it out or use it as a desktop wallpaper, you can do so using your computer.
Open your image file using image software. If you do not have image software, the JPEG Committee has suggested programs such as PaintShop Pro, Adobe Photoshop, and Irfanview.
Select the "Resize" option. The "Resize" option is usually found under the "Edit Pictures" or "Picture" category in the image software's tool bar.
Enter the new larger image size that you prefer. You can enter a customized larger size by inches or pixels, or you can increase the size in proportion to the original image. Unless you know the specific size you need the image, you may want to increase the size by proportion so the image doesn't become distorted.
Save your image. You must select the "Resize" or "OK" button when resizing to apply the changes. Then save your image to complete the process of enlarging the JPG photo.