Monday, September 26, 2016
PowerPoint slides or flipcharts shouldn’t give your audience an eye exam
At the very end of 2005 Guy Kawasaki described The 10/20/30 Rule of PowerPoint which said:
“....a PowerPoint presentation should have ten slides, last no more than twenty minutes, and contain no font smaller than thirty points.”
The 30 point font size is a reasonable minimum. Dave Paradi has discussed Selecting the correct font size in more detail by including both the screen size and maximum viewing distance.
Back in 2008 my blog post on Don’t be a “Flip Chart Charlie” discussed how the same problem can rear its ugly head in flip charts:
“Keep reducing the size of your letters to indicate the headings, sub headings, sub-sub headings, sub-sub sub headings etc. With enough levels you can give your audience a free eye exam.”
In an article posted on April 23, 2014 Tim Themann described Some Data on the Current Use of PowerPoint - Font Sizes which revealed that people unfortunately seemed to follow PowerPoint defaults for hierarchical bullet point lists. Please don’t do that and then ask your audience to read 10 or 12 point letters!
The 1937 eye test image from the W.P.A. Federal Art Project was found at the Library of Congress.