How to resize your images for the web

From NetMusician Wiki

The following guide will help you resize your images so that they are in a web-friendly format.

Windows

You will need to download additional software to resize your images, as this functionality is not included within Windows XP. There are numerous software titles that will handle this task, this guide will provide directions for using Microsoft's "Image Resizer PowerToy for Windows XP".

1. Download the Microsoft Image Resizer PowerToy for Windows XP here (find the download link in the right hand column of this page). After downloading this software, install this software by double clicking on the Installer icon (i.e. the file that was just downloaded).
   
   
2. Right click on the image file you wish to resize, select Resize Pictures.
   
   
3. In the "Resize Pictures" window, click on Advanced.

   

4. Select "Custom" and enter a width in pixels in the first field to constrain the image by width, or a height in pixels in the second field to constrain by height. The width of most webpages is 800 pixels wide, so a good starting place might be a width of 300-400 pixels.
   
   
5. Click on "Make pictures smaller but not larger", and click on OK.

   

6. You can preview your new image by double clicking on the new file created in the same location as original, identified by having "(Custom)" as a part of its filename.

Note: if you wish to increase the size/scale of your new file, it is better to work from the original file, as enlarging an image will often lead to noticeable distortion.

Macintosh

You will need to download additional software to resize your images, as this functionality is not included within Mac OS X. There are numerous software titles that will handle this task, this guide will provide directions for using "GraphicConverter" by Lemke Software.

1. Download GraphicConverter here. After downloading this software, drag the "GraphicConverter" icon out of the disk image which appears on your Desktop, and move it into your Applications folder to install this software.

   GraphicConverter icon

2. Navigate to your Applications folder and open GraphicConverter from this folder, or drag the icon to your dock and open it from there if you anticipate using this software frequently. After a brief pause, you should be able to click on the Try It button. Do so.
   
   
3. From the "GraphicConverter first steps" window, select Open an image... and click OK. Navigate to your image file you wish to resize, and click Open.
   
   
4. You should now see your image inside GraphicConverter. To resize your image, click on your "Picture" menu, navigate to "Size", and select Scale....
   
   
5. Set your "X-Resolution" and "Y-Resolution" to 72, and then enter your desired width or height in inches or centimeters. Click OK.

   

6. From your "File" menu, select Save as.... Give your file a name (different than the original), save location, and set the format to "JPEG/JFIF". Click Save.
   
   
7. You can preview your new image by double clicking on the file you just saved.

Note: if you wish to increase the size/scale of your new file, it is better to work from the original file, as enlarging an image will often lead to noticeable distortion.