The key aspect to reducing your PowerPoint file sizes is to optimise the images in your PowerPoint document. This means reducing the overall image size while retaining reasonable image quality for marking purposes.

The best way to reduce your PowerPoint file sizes is to optimise your images in an image editing program before you import them into PowerPoint. There are many programs you can use to do this.

Some facts & figures:

  • The highest resolution that a digital screen can display is 72dpi
  • All assignments are viewed and e-assessed on-screen
  • Your image dimensions DO NOT need to exceed 1200px in height

How to compress Keynote presentations


  1. Make sure you’ve saved your file before you start (File > Save).
  2. Go to File > Save As and save the file with a different name to help differentiate it from the original version. You might add “reduced” to the end of the file name, for example.
  3. Now that you’re working with this different version, go to File > Reduce File Size.
  4. The file is now compressed but you still have to save it, do so by going to File > Save.
  5. You’re Done! If you’d like to see the difference, have a look at your original file and the reduced file, and compare their file sizes.