Scaling and Sizing image with Graphic Converter (Mac OSX)

Save your image to your hard disk, name it so you will be able to find it in the next steps.

Open Graphic Converter.

Open the image you saved in step 1.

Go to the Picture menu -> Resolution.

Set the resolution to 72 dpi x 72 dpi.

Go to Picture menu -> Size -> Scale.

There is not one correct size to scale your image to. Each 72 pixels are going to represent an inch. So if you want your image to be 4 inches wide, you would set it to about 288 pixels wide. If you are not sure, it is better to leave your image larger rather than smaller. 640 pixels across is a very large size for a web image. On many websites the larger images are about 500 pixels across.

Select File menu -> Save As...

Select a new name for your image so you don't overwrite the original.

The Save dialog box will appear.

Select Jpg and choose a quality level of "90".

Save your image.