Flesch Reading Test

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Readability is the measure of how easy a text is to understand. While readability is not a direct Ranking-It is not the most important factor, but it is related to many user experience metrics, e.g. bounce rate, time spent on the page. These key figures are in turn linked to the Ranking linked, so it is important to pay attention to readability when creating content.

In this post I want to find out how the Flesch Reading Test can be used to analyze and improve readability, and in what ways it can be useful in terms of SEO.

What is the Flesch Reading Test?

The Flesch Reading Test measures the readability of a text in English.

Developed by Rudolf Flesch, the equation has been used in the communications industry since the 1940s and allows authors to optimize the readability of a text to the target audience.

The easier the text is to understand, the higher it is ranked on a scale from 0 to 100. The equation is based on the average number of words and syllables per word.

As a consultant to the Associated Press, Flesch developed a readability rating system for journalists and copywriters to use. He explained his formula in the second Kapition of his book How to Write Plain English:

"Multiply the average sentence length by 1.015. Multiply the average word length by 84.6. Add the two numbers. Subtract that sum from 206.835. The remainder is your readability score."

Flesch also provided a table to help interpret the scores.

Nowadays the Flesch Reading Test one of the most popular measurements of readability. In the world of news and advertising copy, it has proven to provide reliable findings that transfer well to different types of text.

How does the Flesch Reading Test work?

The Flesch Reading Ease Test is a simple algorithm that measures the readability of a text. This test was developed by Rudolf Flesch and is based on the assumption that the less school knowledge the reader needs to understand a text, the easier it is to read. The test calculates a readability index on a scale of 0-100, with higher values indicating higher readability.

The test is based on two factors:

  1. Number of words per sentence: A text that contains shorter sentences is easier to read than a text with longer sentences.
  2. Number of syllables per word: A text that contains shorter words is easier to read than a text with longer words.

In order to Flesch Reading Ease test, these two factors are inserted into a formula:

Readability index = 206.835 - (1,015 x words per sentence) - (84.6 x syllables per word)

The readability index calculated by this formula can then be converted to the following scale:

  • 100-90: Very easy to read
  • 89-80: Easy to read
  • 79-70: Moderately easy to read
  • 69-60: Somewhat difficult to read
  • 59-50: Hard to read
  • 49-0: Very difficult to read

It is important to note that the Flesch Reading Ease test is only one indicator of the readability of a text and does not take into account all aspects of readability. There are also other factors that can influence readability, such as the use of technical terminology or the structure of the text. It is therefore important to consider the Flesch Reading Ease Test to be considered as one of several methods for evaluating readability.

How to achieve a good Flesch Reading Score

Here are some tips on how you can get a good Flesch Reading Score:

  1. Use short sentences: Long sentences can be difficult for readers to understand. Therefore, try to keep your sentences short and concise. A good rule of thumb is that a sentence should not be longer than 15 to 20 words on average.
  2. Choose simple words: Use simple and understandable words instead of complicated technical terms or foreign words. If you find an easier synonym for a difficult word, use it.
  3. Active instead of passive: Write in the active, rather than the passive voice. This means that the subject of an action is in the foreground and performs the action. For example, "The dog chases the cat" instead of "The cat is chased by the dog." Active sentences are usually shorter and easier to understand.
  4. Paragraphs and bulleted lists: Structure your text into clear paragraphs and use bulleted lists to present information clearly and understandably. This makes it easier to read and understand the text.
  5. Avoid nested sentences: Try to avoid nested sentences and convoluted subordinate clauses. They can disrupt the flow of reading and make the text difficult to understand.
  6. Variance in sentence structure: Use different sentence structures and lengths to make your text interesting and easy to read.
  7. Make clear statements: Avoid vague or imprecise wording. The clearer and more direct your statements are, the easier it is for readers to understand the text.
  8. Revise text: Read through your text several times and revise it to remove unnecessary repetitions, complex phrases, or incomprehensible passages.

By following these tips, you can improve the readability of your text and achieve a good Flesch Reading Score.

Results of the Flesch Reading Test

The Flesch Reading Ease Test calculates a readability index on a scale of 0-100, with higher values indicating higher readability. The Index can be converted into different readability grades, which describe the readability of a text.

The following readability grades are used in the Flesch Reading Ease Test used:

  • 100-90: Very easy to read. This text is understandable for everyone, including children and people with little school knowledge.
  • 89-80: Easy to read. This text is understandable for most adults, but it may be difficult for some people with little school knowledge.
  • 79-70: Moderately easy to read. This text requires some school knowledge to be fully understood.
  • 69-60: Somewhat difficult to read. This text requires a certain amount of school knowledge and attention to be fully understood. It may be difficult for some people with little school knowledge or attention to understand.
  • 59-50: Difficult to read. This text requires high school knowledge and a lot of attention to be fully understood. It is likely that only people with advanced school knowledge and high attention will fully understand it.
  • 49-0: Very difficult to read. This text requires a very high level of school knowledge and attention to be fully understood. It is unlikely that anyone without advanced school knowledge and high attention will fully understand it.

It is important to note that these readability grades are only guidelines and are not equally applicable to every text. There are also other factors that can influence readability, such as the use of specialized terminology or the structure of the text.

Tools for calculating the Flesch Reading value

There are a number of tools that you can use to make the Flesch Reading Ease Test to perform on your texts. Here are some of the most commonly used tools:

  1. Microsoft Word: Microsoft Word includes a function to perform the Flesch Reading Ease Tests. You can access the readability statistics via the "Review" tab and then "Readability".
  2. Online tools: There are many online tools that you can use to help Flesch Reading Ease Test to perform. Some examples are "Readability Test Tool" and "Online Readability Formula". These tools only require you to paste the text and the results are calculated automatically.
  3. Plugins for content management systems: If you have a Content Management System (CMS) like WordPress, there are plugins that you can install to make the Flesch Reading Ease test on your website. An example of such a Plugin is "Yoast SEO", which, among many other functions, also evaluates the readability of your texts.
  4. Google Docs Add-Ons: There are also add-ons for Google Docs that make it easier to perform the Flesch Reading Ease enable tests. One example is "Readability Score", which gives you a readability index and detailed analysis of word and sentence length.
  5. Programming libraries: If you are developing your own application or script, there are also programming libraries that you can use to use the Flesch Reading Ease test to be performed. Examples of this are the Python library "textstat" and the JavaScript-library "readability-js".

It is important to note that these tools are based on the calculation of the Flesch Reading Ease test and there may be differences in the results. It is therefore important to use several tools to get a more accurate assessment of readability.

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FAQ

What is a Flesch index? arrow icon in accordion
The Flesch index is a measure of the readability of a text. It is calculated by counting the number of words, the number of sentences, and the number of syllables in a text. The index indicates how easy a text is to understand. A high Flesch index means that the text is easy to read, while a low Flesch index means that the text is difficult to read.
How is the Flesch index calculated? arrow icon in accordion
The Flesch index is calculated by counting the number of words, the number of sentences, and the number of syllables in a text. The index is then expressed as a percentage. The higher the percentage, the easier it is to understand the text.
Why is the Flesch index important? arrow icon in accordion
The Flesch Index is a useful tool for determining whether a text is easy to understand and read. It is important that texts are easy to understand, especially if they are aimed at a wide audience. The Flesch Index helps authors write texts that are easy to read and understand.
What does a high Flesch index mean? arrow icon in accordion
A high Flesch index means that the text is easy to read. A text with a Flesch index of 80-90% is easy for a wide audience to understand. The Flesch index can also be used to convey complex ideas in a way that is easy for a wide audience to understand.
Which Flesch indexes are considered "easy to read"? arrow icon in accordion
A Flesch index of 90-100% is considered easy to read. A text with a Flesch index of 80-90% is easy to understand for a wide audience. An index of 70-80% is considered "moderately difficult to read" and an index of 60-70% is considered "difficult to read".
Is a high Flesch index always better? arrow icon in accordion
No, a higher Flesch index is not always better. In some cases, a lower Flesch Index can make the text easier to read and understand when dealing with more complex ideas or concepts. The Flesch Index is only one tool to measure the readability of a text; ultimately, the decision of what is easy to read is up to the author.
Can different versions of a text have different Flesch indexes? arrow icon in accordion
Yes, this is possible. When a text is revised to be easier to read, the Flesch index may vary. By changing words, sentences and syllables, the index can vary.
Can different types of texts have different Flesch indexes? arrow icon in accordion
Yes, it is possible that different types of texts have different Flesch indexes. Since the Flesch index is based on the number of words, sentences, and syllables, it can vary depending on the type of text. Technical texts usually have lower Flesch indices than popular science texts because they contain more complex ideas.
Is it possible to calculate the Flesch index yourself? arrow icon in accordion
Yes, you can calculate the Flesch index manually by counting the number of words, sentences and syllables in a text. There are also many online tools that do this automatically.
Can Flesch indices be calculated for all types of texts? arrow icon in accordion
Yes, Flesch indices can be calculated for all types of texts, including technical texts, popular science texts, novels, poems and more. The Flesch Index is a universal tool that can be used for all types of texts to determine how easy a text is to understand.

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