Why Is the Flesch Readability Score Important for SEO Strategy?

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Why Is the Flesch Readability Score Important for SEO Strategy?

Readability determines how easily your target audience is able to engage with your text. Making sure that your text is readable will keep visitors on your site page for longer. This is because they will find the information they’re looking for more easily. Readable content is more likely to be shared and revisited, and site visitors are more likely to explore other areas of your site.

Besides that, a site that isn’t readable doesn’t sound like an authority on the subject. Your reader needs to be confident in the information you’re providing. Good writing and grammar will ensure you sound professional.

Search engines know and consider this. Failing to make your copy readable will have a negative impact on your SEO ranking. However, even well-written copy can be hard to read. This is where the Flesch Readability Score comes in. Read on to find out how the Flesch score can help you make sure your website copy is engaging for your audience, and improve your SEO rankings.

  • 1. What Is the Flesch Score?
  • 2. How Is It Calculated?
  • 3. How Can I Test My Copy for Flesch Reading Ease?
  • 4. Why Does My Score Matter?
  • 5. What Flesch Score Should I Be Aiming For in My Web Copy?
  • 6. How to Improve Your Readability Score

1. What Is the Flesch Score?

The Flesch Reading Ease formula gives your text a score between 1 and 100, with 100 being the most readable. The formula was developed in the 1940s by Rudolf Flesch, who was developing methods to help improve the readability of newspapers. Now, the Flesch formula is used in many different sectors to ensure that text is accessible and will be engaged with.

Engaging and readable copy is likely to perform best in search rankings – much like how in the 1940s, you might have reached for the most engaging newspaper.

2. How Is It Calculated?

The score is based on the number of words per sentence and the number of syllables per word. Here is the formula:

206.835 – 1.015 (total words / total sentences) – 84.6 (total syllables / total words)

So, your score will be lower if you use longer sentences and longer words because these are harder to follow.

2.1. Flesch Kincaid Grade Level

The Flesch Kincaid Grade Level is a great way to put your Readability score in context. It matches your score to a US grade level of education. Here is the formula:

0.39 (total words / total sentences) + 11.8 (total syllables / total words) - 15.59

3. How Can I Test My Copy for Flesch Reading Ease?

3.1. Online Tools

Don’t worry, you don’t need to dust off your calculator for this one. There are plenty of online tools that will calculate your score for you, like this one by WebFX.

Online tools that will calculate your score for you

Here, the tool has reassured me that my blog post is readable enough. As you can see, a mid-range Flesch score equals a suitable Flesch Kincaid Grade Level.

Online-Utility.org will provide you not only with your Flesch score but also with your average words per sentence, syllables per word, and a list of sentences to consider changing. So, this tool might be best if you want specific steps to improve readability without installing a plug-in.

3.2. SEO Plugins

The quickest and easiest way to continually monitor your text’s readability is to use a plugin. This will also help you tailor your writing to fit your keyword strategy. The free Yoast plugin for WordPress sites will help you check your Flesch score as you write.

Yoast plugin

As you can see, Yoast assesses your copy for things like paragraph length and how many transition words you use. It’s extra handy because it provides you with actionable steps to make your text more readable.

However, you don’t need to satisfy all of the criteria to achieve good readability. Perhaps the topic you’re writing on requires a couple of specific, jargon words that you can’t shorten or simplify. You can easily compensate for this in other aspects of your writing.

4. Why Does My Score Matter?

You might be thinking that sure, readability sounds important for user experience. But maybe you feel that your content is already accessible enough. Pausing to assess your Flesch score can help identify areas in which you could improve your writing. More than this, it will ensure your writing is properly tailored to your audience.

4.1. User-friendly

Certain SEO plug-ins like Yoast will have you aim for at least in the high 50’s. But why? It can seem counterproductive to tailor your writing for SEO rather than your audience or to feel like you are ‘dumbing down’ your writing. But really, ensuring your writing is more readable makes it more human-friendly as well as SEO-friendly.

Yoast gives two reasons why SEO is important. They believe in a holistic approach to SEO, meaning that a good user experience is better for search engine rankings. Secondly, they argue that if your content is easily readable, your site visitors will spend more time on your pages, and they will come back to them.

4.2. Accessibility

Readability can make your copy more inclusive, for example, subheadings can make your text easier to follow for those with learning difficulties like dyslexia. Titling your text and adding alternative text for images will also make your text readable for visually impaired readers, who will use audio transcribing software.

Explore why HTML headers are important for SEO: ‘How to Use HTML Headers for Better SEO Performance.’

5. What Flesch Score Should I Be Aiming For in My Web Copy?

Aim high but not too high – you want your writing to be accessible, but it doesn’t need to be read by kindergarteners. However, the average reading age might be lower than you would expect.

The Flesch Kincaid Grade Level is useful for matching your readability score to your intended audience. Text that’s meant to be read by the general public should aim for a grade level of about 8, which is equivalent to a schooling age of 13 to 14. Text matching this age can be read by around 80% of Americans.

6. How to Improve Your Readability Score

It’s all about balance. You don’t need to hit every single one of these guidelines, but using them to guide your writing will go a long way.

  1. Shortening sentences: Break up your clauses to make them easier to follow. Take this example:

Shortening your sentences is extremely important, both for your SEO rankings and for reader accessibility, hence you should endeavour to break them up in order to create a better user experience.

Pretty boring right? Let’s try again:

Longer sentences are hard to follow. This can cause your SEO rankings to drop, as your readers won’t engage with your content. So, break up your clauses for a better user experience.

  1. Using less complex words: Don’t use jargon or long words where they aren’t needed. This will obviously depend upon your audience and topic, but where there’s a simpler synonym available, go for it.
  1. Transition words: these are words that help to bridge sentences or paragraphs together. They can help leaders to link related information together, as well as provide structure to your text.

Yoast recommends that 30% of your sentences should include these. More often than not, you can make your point without a transition word. But going out of your way to include them can make your copy flow better. Let’s look at some examples.

I’m not much of a dog person. I really love cats. / I’m not much of a dog person. However, I really love cats.

A lot of people think black cats are unlucky. Many of them end up in shelters. / A lot of people think black cats are unlucky. Because of this, many of them end up in shelters.

  1. Active voice: this is normally more direct and authoritative than passive voice. In the active voice, the subject acts. Whereas in the passive voice, the subject receives the action. Of course, there will be some instances where passive voice is best, but if you can avoid using it, do so. Here’s an example of how active voice can be more engaging:

Active: Daniel passed the salt.

Passive: The salt was passed by Daniel.

More often than not, the passive voice adds unnecessary words and skirts around your point.

  1. Using H2-H6 headings: these will help your reader to find specific information more easily, and keep them engaged by breaking up large chunks of text. Distribute headings evenly and ensure that you use your targeted keyword throughout different heading levels.

💥 Handy hack: To gather all H1-H6 headings from your website / blog quickly and easily, you can use the Nepteak Spider crawler and:

  1. Enter a website’s URL into the ‘Initial URL’ field.
  2. Go to the parameters in a sidebar and find the ‘Content’ group → select ‘H1-H6’ (or the ones that you need) and start crawling.
  3. Voila! All the results are gathered in the main or database table, which you can export into Excel tables or Google Sheets for further analysis.

BTW you can collect HTML headings and other meta tags even in the free version of Netpeak Spider crawler that is not limited by the term of use and the number of analyzed URLs. Other basic features are also available in the Freemium version of the program.

To get access to free Netpeak Spider, you just need to sign up, download, and launch the program 😉

Sign Up and Download Freemium Version of Netpeak Spider

P.S. Right after signup, you'll also have the opportunity to try all paid functionality and then compare all our plans and pick the most suitable for you.

  1. Concise content: if readers don’t find the information they want from you right away, they will leave your site and look elsewhere. Search engines can detect a high bounce rate and work out that your page isn’t giving visitors the answers they’re looking for. This can negatively impact your rankings. Keep your articles concise, with the most important information at the start. Don’t include anything that you don’t need to.


The Flesch Readability score is a solid tool for checking how accessible and engaging your web copy is. Making sure that your text is easily readable will not only keep site visitors on your web pages for longer. It can also improve your search rankings as you appear more authoritative on the subject, and site visitors can find the information they’re looking for more easily. So, the Flesch Readability score is a great way to check that your web copy is consistently readable and is a vital part of any on-page SEO strategy.