Compressing Image Files in Powerpoint Presentations

So I've been working at the Computer Help Desk of my university lately, and I've run across a professor who constantly needs the file sizes of his Powerpoint presentations to be compressed.

Now, we're talking presentation file sizes in the range of 100 - 300 mb! I was shocked when I first saw this, because I didn't even know it was possible to make a Powerpoint that large. The main culprit of the ginormous file size? The images contained within the presentation.

Fortunately, I was able to help him. I decided to post the solution online here as well, for others who may face similar problems.

You see, he had been dragging and dropping Bitmap (.BMP) images from his scanner and digital camera directly into Powerpoint. Those raw, uncompressed files were embedded in the presentation, and taking up a great amount of space. When working with Powerpoint, doing this is very inefficient, and can slow Powerpoint down to a crawl when working on slides with the huge images.

Fortunately, there is an easy way to compress these existing images using Powerpoint itself. Note, this does NOT require any third party software to accomplish. The necessary tools are already present in Powerpoint. AFAIK, this can be done in Powerpoint 2003 and Powerpoint 2007, but I'm not sure about previous versions.

Look for any image(s) you suspect may be large in file size. If you imported some images directly from a scanner or digital camera, go for those images first, because they are more likely the ones causing the problem. Images gathered from the web (clipart, things found on Google Images) are not usually that large in size, so those wouldn't be a problem.


Now, let's right-click on the image and go to Save As Picture. Save the file in any location you want, as long as you can find it later. The file we save here will not be needed after we finish working in Powerpoint, so go ahead and save in a location you can remember. When saving, ensure the file type "JPEG" is selected in the dropdown box. Powerpoint will then save the file as a highly compressed JPEG, getting rid of any excess information. Note that the clarity of the images will not be affected at all during this process!

Now let's go back into Powerpoint, right-click on the same image and select Change Picture. Find the file you just saved somewhere on your computer, and import that back in. Notice that the image itself has not changed at all - but it is now as compressed as possible!


If the Change Picture option is not available, you will need to manually re-import the saved file. Delete the image out of the powerpoint slide, and go find the compressed file you just saved on your computer. You can now drag-and-drop that image file into Powerpoint, or (in Powerpoint 2007) click on the Insert tab, and choose Picture. Either way, you will get the newly-compressed picture back into your slide.

Lastly, check the file size of your slide show in Windows Explorer. If it's gone down quite a bit - congratulations, you've just eliminated some bloated images from your presentation!


Note that many other applications like Adobe Photoshop, IrfanView, or even Microsoft Paint can accomplish file compression tasks. But with the way Powerpoint has it set up, it is much more streamlined, and takes less time.

I hope this tutorial has taught you something about file compression / saving features in Microsoft Powerpoint!