1. Press "Start", select "All programs", then select "Accessories" and finally open "Paint".

2. Press "CTRL"+"O" to open the image which you want to resize.
3. Press "Resize" button.


4. You can resize image by percentage or by pixels. If "Pixels" is selected, you can enter the the desired image size. If you are going to upload the resized image to your website, there is no point in having bigger image than 800x600px as bigger images take much more time to load and most of the times you will not be displaying the actual size of the image. For example if your image is a landscape photo, you just need to enter the width 800px and make sure that the "Maintain aspect ratio" is checked. The height will be done automatically. If your picture is a portrait picture, just enter the height 600px and the width will be done automatically as long as "Maintain aspect ratio" is checked.

5. Press "CTRL" + "S" to save your image.
That's the way you can resize image's using Microsoft Paint.