This document discusses the readability of uppercase versus lowercase letters. It presents evidence that lowercase letters are more readable than all uppercase letters for long texts. Specifically, a study found reading speed was 10% slower when text used all capital letters compared to lowercase. The document encourages applying this finding by identifying situations where readability is an issue and avoiding all uppercase text.

1. Uppercase versus
lower-case letters
Prepared by J. Scott Armstrong (details on him at jscottarmstrong.com).
Please inform Scott about errors and also make suggestions (armstrong@wharton.upenn.edu)
Scott has taken these slides from adprin.com, a site that he founded. That site contains interactive versions of these
slides, along with linked references, videos, and webcasts, all in PPT and PPTX format that you can download.

2. Uppercase versus lowercase letters
Can you read this passage? It shows the top half
of the letters when capitals are used.
Adapted from AdPrin.com 2

3. Here is the same passage but with the top
halves of lower case letters. Is it easier for you
to understand?
Note that the shapes of the lower-case letter are more
informative. This has been used as an argument for why
lower case is easier to read.
Adapted from AdPrin.com 3

4. Evidence
A study using 40 readers found that when all
letters were capitalized in long text, reading
speed was 10% slower than when lower-case
letters were used (See Persuasive Advertising p 261).
To learn more, see AdPrin.com

5. Based on this exercise, write a small application step for yourself,
and set a deadline, preferably within one week. If you are
working with someone else, share your application plan and the
results of your application.
• For example, identify situations where readability is an issue
and avoid uppercase.
Adapted from AdPrin.com