Readability

What is a readability formula?

Readability formulas use math to show how easy your document is to read. Each formula listed below is different. All of the formulas have the same goal: to help you simplify your documents.

 

Why should I use a readability formula?

Many people in Iowa and the United States cannot read at more than an eighth grade level. However, health information has traditionally required a college graduate reading level. This can create confusion and prevent people from having good health.

Readability formulas tell you the reading level needed to read your document. This allows you to change your writing so that more people are able to read it. This then leads to better health.

 

How do you determine the readability of your document?

Select one of the formulas below to calculate your document's readability. The formulas will either give you a level of reading ease or a school grade level.

This is not an exact science. Different formulas will give you different answers. We encourage you to try each formula to see what fits your needs. When you find a formula you like, use it consistently when editing your document to be more readable.

 

Which formulas are used the most?

• Bormuth Index  
• CLEAR   Online Readability Calculator from WordsCount
• Flesch Reading Ease  
• Click here to learn about the Flesch Reading Ease Formula  
• Flesch-Kincaid Grade Level  
• Click here to learn about the Flesch-Kincaid Grade Level  
• Gunning-FOG Index  
• Click here to learn about the Gunning-FOG Index  
• Fry's Readability Graph  
• Click here to learn about Fry's Readability Graph  
• SMOG Formula  
• Click here to learn about the SMOG Formula  
• Spache & Dale-Chall indexes  
• Combined Tools with Averaging Function for Automated Readability Index, Coleman-Liau, Flesch-Kincaid, Gunning-Fog, and SMOG
• Combined Tools for Automated Readability Index, Coleman-Liau, Flesch-Kincaid, and SMOG
• Combined Tools   from WordsCount for SMOG, Gunning-Fog, Automated Readability Index, Coleman-Liau, Flesch-Kincaid, Spache and Dale-Chall.

Related Resources

• Project to Review and Improve Study Materials (PRISM) is a Group Health Center for Health Studies initiative to improve the readability of print materials used in communication with study participants.  

 

Questions or contributions? Contact Don McCormick at 515-281-6692 or use the Contact Us page to submit your question.

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