Change the slide size in a presentation

On the Design tab, select  ​​​​​​​ Slide Size.

Select Standard (for slides with a 4:3 aspect ratio) or Widescreen (for a 16:9 aspect ratio).

On the Design tab, select  ​​​​​​​ Slide Size.

Select Standard (for slides with a 4:3 aspect ratio) or Widescreen (for a 16:9 aspect ratio).