Change the size of your slides - Microsoft Support

Use Widescreen (16:9) or Standard (4:3) or choose a custom size for your slides.

Powerpoint Presentation Sizes Sale

Change the size of your slides - Microsoft Support

Change the size of your slides - Microsoft Support

Create or change a presentation's handout - Microsoft Support

Add a background picture to slides - Microsoft Support

Change the font size - Microsoft Support

Create or change a presentation's handout - Microsoft Support

What Slide Size Should You Use? Presentitude, 59% OFF

Add color and design to your slides with Themes - Microsoft Support

How to Change the Slide Size in Google Slides - Tutorial