Reducing the size of a PowerPoint slideshow

PowerPoint can compress images and remove unneeded data

(Note: This does not change the original pictures you put into PowerPoint, just the versions stored in the PowerPoint itself.)

1. Locate a slide that has a picture on it, and view that slide. 
2. Select the picture by left+clicking once.
3. Click on the Format tab under the Picture Tools Heading
4. On the Format menu, locate the Adjust group and click on Compress Pictures
5. On the Compress Pictures dialogue box, you can check the options for compression by clicking Options
   • Compression Options:
     • Automatically perform basic compression on save - this setting can remain checked and can help reduce the size of your presentations when you save.
     • Delete cropped areas of pictures - this setting can remain checked. This allows PowerPoint to delete areas of larger photos that you have decided not to display by cropping them within the presentation itself.
   • Target Output:
     • Print (220 ppi) - use this setting for compressing a presentation that has pictures you plan to print. This can still reduce the size of your presentation without losing the quality necessary for printing
     • Screen (150 ppi) - use this setting for compressing a presentation that you plan to show on the screen. This is the setting you should use most often.
     • E-mail (96 ppi) - use this setting for compressing a presentation that you would like to share, possibly via email. This setting might help make a larger presentation small enough to email, but generally is not needed in order to save space.
6. Click OK on the Compression Settings dialogue box once you have made the necessary selection.
7. Click OK on the Compress Pictures dialogue box.
8. Wait for the compression to finish, and then save your presentation. 

What resolution should I make my images for PowerPoint slide shows?

In most cases, images don't need to be much larger than 1024 × 768 pixels (see below to learn why). If your images are larger than this, your PowerPoint files are probably bigger than they need to be. Reducing their size makes PowerPoint presentations use less disk space, load quicker, and easier to manage.

Most projectors use the resolution of 1024 x 768 pixels (dots on the screen), so it's a good choice when in doubt. The images won't be large enough to slow things down even if your presentation is shown on lower resolution displays. Still, the images will look acceptable on higher resolution setups.

Keep in mind that this advice applies to images in PowerPoint screen shows. It'll also give you good results on most desktop printers. But, for poster printouts, 35mm slides, and other high resolution output, you'll want to start with higher resolution images. Just don't go overboard; the higher the resolution, the larger the image files; the larger the image files, the larger your PowerPoint files will become, and the slower the images will display. You want your images to be just big enough to look good and not a pixel bigger.