Get your email's readability and level statistics (2024)

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When Outlook finishes checking the spelling and grammar and errors corrected, you can choose to display information about the reading level of the document, including readability scores according to the Flesch-Kincaid Grade Level test and Flesch Reading Ease test.

Go to File > Options.
Select Mail, and then, under Compose Messages, select Spelling and AutoCorrect.
Select Proofing.
Under When correcting spelling in Outlook, make sure the Check grammar with spelling check box is selected.
Select Show readability statistics.

After you enable this feature, open a message that you want to check, and check the spelling. When Outlook finishes checking the spelling and grammar and errors corrected, it displays information about the reading level of the document.

Understand readability scores

Each readability test bases its rating on the average number of syllables per word and words per sentence. The following sections explain how each test scores your file's readability.

Flesch Reading Ease test

This test rates text on a 100-point scale. The higher the score, the easier it is to understand the document. For most standard files, you want the score to be between 60 and 70.

The formula for the Flesch Reading Ease score is:

206.835 – (1.015 x ASL) – (84.6 x ASW)

where:

Flesch-Kincaid Grade Level test

This test rates text on a U.S. school grade level. For example, a score of 8.0 means that an eighth grader can understand the document. For most documents, aim for a score of approximately 7.0 to 8.0.

The formula for the Flesch-Kincaid Grade Level score is:

(.39 x ASL) + (11.8 x ASW) – 15.59

where:

ASL = average sentence length (the number of words divided by the number of sentences)

ASW = average number of syllables per word (the number of syllables divided by the number of words)