Presentation Crash Course #2: Choosing the right aspect ratio

by Improve Presentation Last Updated: 2018.08.01

(If you’re just joining the Weekly Presentation Crash Course by Improve Presentation, you might want to start at the beginning!)

What is aspect ratio?

The ratio between picture width and picture height. This ratio can be maintained even when resizing a picture. Most templates use either 4:3 or 16:9 aspect ratio.

Big-screen presentations, such as major keynote addresses at conferences, often use templates with a 16:9 aspect ratio. The dimensions of templates with a 16:9 aspect ratio vary depending on the screen-projection requirements, but they are almost twice as wide as they are tall.

aspect ratio

Why should I care?

In PowerPoint 2013 the slide layout area is now default 16:9 widescreen, so as soon as you start a new presentation your area dimensions are set like this as standard. All previous versions of PowerPoint default to a 4:3 ratio.

Most screens we use to view our presentations are now a 16:9 widescreen dimension:

  • Laptops – 16:9 widescreen
  • Plasma/LED TVs – 16:9 widescreen
  • Projectors – newer models are using a 16:9 widescreen.
slide size defaults

Determining the correct aspect ratio for your presentation should be top on your list before any slide development starts.

Widescreen, with its 16:9 aspect ratio, is taking over video screens faster than Godzilla in a scale model city. And that’s a good thing.

What is the aspect ratio of your presentation?

You can check & change the aspect ratio of your presentation quite easy.


To configure a special Aspect Ratio for your slides, you will need to go to Design tab and then press Page Setup.

page setup powerpoint

This will open a new Dialog showing the Page Setup options. Here you can choose Slide Sized for different screen types and resolutions, and you can also set the page width in inches or page height.

aspect ratio powerpoint


To change the slide size to custom size, click on the Inspector – the blue icon with an i. Click Document on the document inspector, select slide size. You can also enter a custom width and height there. See the image below for reference.

slide size keynote

If you try to open a 4:3 presentation in 16:9 aspect ratio your slides might look stretched.

powerpoint change format

Will your presentation be projected at 4:3 or widescreen? If you change to another aspect ratio midstream, graphics will stretch or distort, type sizes may change, text boxes can move out of position, etc. Slides will need to be reformatted and all graphics resized and repositioned — a time-consuming job.

You can probably get the quickest answers to these questions by consulting with your AV team or event site coordinators.

This is a blog written by Improve Presentation. We are presentation experts. We design high quality Powerpoint Templates and Keynote Templates and create custom unique slidedecks for our clients. See our work