This article describes a method of resizing images using programs that come with your computer. Such programs are Paint for Windows and Preview for Mac.
Windows 7, 8 and 10:
To Resize an image, open up the image through Paint. Right click on the image and go “Edit”. This will open Paint with the image.
Once in Paint select “Resize” in the home menu as seen to the right:
This will open a new window with a variety of options of resizing the image.
Once completed, save the image by selecting the blue button on the top left of the screen and going save, or by using the hot keys "ctrl"+"s".
Open an image in Preview. Preview is the basic image viewing program that comes standard with Mac. Usually this just involves double clicking the image.
Once you are looking at the image, select Tools on the Apple menu bar and select “Adjust Size”. This is shown in the image below:
You will now be able to resize by percentage, pixels, metric or imperial. You will also be able to proportionally resize.
Once completed save the image by going File from the Apple menu and selecting Save. Or use the hotkeys "Command" + "S".