How to Improve the Readability of Your Business Writing with Flesch Reading Ease Scores


A quick and simple way to improve your business writing is to measure its readability. Measuring your business writing might sound strange, but it is an objective way to analyse your business writing.


Before showing you how to apply the concept of readability to your business writing, I’ll explain what it is.


Standards for measuring readability of texts date back to the 900s AD when students of the Jewish body of laws, the Talmud, counted the occurrences of words and ideas in order to distinguish differences in meaning. The result was an early attempt to measure readability.


Modern research into readability began in the 1920s when Thorndike published a list of English words used more frequently in texts. It was assumed that a word used more frequently became more familiar to readers and, therefore, easier to read. During the 1920s, the research focused on word factors that could be used to predict readability. In the 1930s and 1940s, the research broadened and led to the derivation of formulas that could accurately predict readability using a minimum number of factors.


Shortages of newsprint during World War II resulted in thinner newspapers with more tightly written articles. During this time Robert P. Gunning developed the Fog Index that counted number of words and the frequency of multi-syllabic words in an article. He told his clients, ‘Write as you talk…Why should a police reporter say an accident victim suffered “contusions and abrasions” when he really means “cuts and bruises?” This idea can be applied to business writing.


There are more than 40 formulas that measure readability. Two that are most widely used today are Flesch-Kincaid Grade Level and Flesch Reading Ease. These can be used to measure the readability of your business writing.


Rudolph Flesch developed these two standards in the 1940s. They are calculated using the average number of syllables per word and the average number of words per sentence. The Flesch-Kincaid Grade Level formula gives a score between the numbers 1 and 12, corresponding to school grade levels in the United States. The Flesch Reading Ease formula gives a number score between 1 and 100. The higher the score, the greater the readability. Most

written materials range between 60 and 70 on this scale. Both formulas are summarised and defined in mathematical terms as follows:


Flesch Reading Ease = 206.835 – (1.015 x ASL) – (84.6 x ASW)



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).


The Flesch-Kincaid formula converts the Reading Ease Score to a school year level (1 to 12).


Flesch-Kincaid Grade Level = (.39 x ASL) + (11.8 x ASW) – 15.59




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).


The formulas are based on the fact that greater average words per sentence and greater average syllables per word make the text more difficult to read. You can calculate the formulas once you know the average words per sentence and average number of syllables per word.


In the past, before widespread access to personal computers, you had to count the words and syllables in your business writing to determine ASL and ASW.


Fortunately, you can analyse your business writing at the end of Spelling and Grammar check in Microsoft Word. First you need to check your settings in Microsoft Word.


Select Options in the Tools menu. In Options select the Spelling and Grammar tab. In the Grammar section of the box select both the Check grammar with spelling and the Show readability statistics boxes. With these options enabled, the readability statistics of your business writing will automatically appear at the end of the Spelling and Grammar check .

 There are also a number of websites where you check the readability of your business writing. One of them is .

Simply copy and paste your business writing into the tool to analyse its readability.


Text for a general readership should have a minimum Reading Ease score of 40. If you examine Australian newspapers such as The Age and Herald Sun, their articles have Flesch-Kincaid Grade Levels between 10.0 and 12.0 and Flesch Reading Ease scores between 44 and 60. Most of the writing in these publications is accessible to readers who have successfully completed a secondary education. In most cases, you’ll want to keep your business writing in a similar ranges on the readability scales.


Applying readability to business writing


When writing for business, you should strive for a Flesch Reading Ease of 40 or greater. You do this by using simple words instead of complicated ones and replacing phrases with single words when possible.

Another key is to write short sentences in your business writing. The Readability Statistics box shown above displays the average sentence length. Effective business writing has an average sentence length of 20 or fewer words. It’s also to important to vary sentence length when business writing. You might have some 30-word sentences and you might have some 5-words sentences in your business writing, but aim for an average of 20 or fewer words per sentence.

(See for explanations on using simple words and short sentences.)


You don’t want your business writing to resemble legal, technical, scientific documents, which are notoriously difficult to read. Many government tax publications, insurance policies and legal documents are written at a PhD level. You don’t want to do this in your business writing.


Many organisations are now promoting plain language documents using Flesch-Kincaid analysis as a guide. The Texas Office of Consumer Credit Commissioner shows samples of documents on its website highlighting the differences between traditional and plain language versions. The traditional version of a home equity loan contract consists of 139 words and has a very low Flesch Reading Ease score of 12.7.

Unless applicable law requires a different method, any notice that must be given to me under this Note will be given by delivering it or by mailing it by first class mail to me at the Property Address above or at a different address if I give the Note Holder a notice of my different address.
Any notice that must be given to the Note Holder under this Note will be given by delivering it or by mailing it by first class mail to the Note Holder at the address stated in Section 3(A) above or at a different address if I am given a notice of first class mail to the Note Holder at the address stated in Section 3(A) above or at a different address if I am given a notice of that different address.


A plain language version conveys the same information but contains only 42 words and has a high Flesch Reading Ease of 73.7.

You or I may mail or deliver any notice to the address above. You or I may change the notice address by giving written notice. Your duty to give me notice will be satisfied when you mail it by first class mail.


Plain language is also best for business writing. Consumers, business people, and other readers don’t have the time for wordy business writing.


Let’s look at an example to show you have to make your business writing more readable.

Drawing back on our years of experience in consulting to businesses in array of issues, from ISO 9001 to business design and strategy, we developed a unique methodology that offers you a real quality solution for your ISO needs, without the expensive price tag that is usually attached to quality ISO 9001 systems.


This sentence has a Flesch Reading Ease score of zero. Let’s rewrite to see if we can improve the readability of the business writing.

We have drawn on extensive consulting experience ─ from ISO9001 to business design and strategy ─ to develop a unique methodology that offers a quality solution to your ISO needs. We provide this without the typical high cost of quality ISO 9001 systems.


After a quick rewrite we have raised the Flesch Reading Ease Score from 0 to 27 out of 100. We also reduced the average sentence length from 53 to 21 words, and lowered the total word count by nearly 20 per cent ─ from 53 to 43.


Readability formulas can be an effective tool to analyse your business writing for its suitability for your audience. These formulas have existed, in some form, for over one thousand years. With personal computers they are very easy to apply and can greatly improve your business writing.