This post was originally posted on August 5, 2013 on Sketchbook B. It’s reposted here as part of a project to move some of my favorite writing to my new site.

A little math problem for you…

One 15-minute PowerPoint1 presentation has 5 slides. Another 15-minute PowerPoint presentation has 15 slides. Which presentation is shorter?

Equal sign projected on a green striped wall

Obviously, both are 15-minute presentations. They are the same length.

But time and again, I talk to people who reduce the number of slides in their PowerPoint because they want to make the presentation “shorter.” They think that if they have fewer slides, they will talk for a shorter amount of time. Often, they don’t take material out, as much as they condense it on the remaining slides.2

That’s completely the wrong way to think about it.

Next time you have a presentation, think about how long you have to present and build your story to fill the allotted time. Then create an appropriate number of slides to support your presentation. You may have more slides and move through them quickly. Or only a handful of slides.

But remember that the length of your presentation has almost nothing to do with how many slides you have.

Bob Wertz is a creative director, type designer, Ph.D. student and researcher living in Columbia, South Carolina. He’s been blogging since 2008.

  1. This applies to you even if you are using Keynote, Prezi or a PDF. ↩︎

  2. I’ve seen people cut slides and have their presentations grow longer, rambling as they try to squeeze in all that they’ve “cut.” ↩︎