What is readability?

When discussing readability, it refers to how easy or difficult it is to read a piece of writing. The score is influenced by factors like sentence structure, word choice, and overall organization of the text. The overall purpose of improving readability is to make written content more accessible to a wider audience, regardless of their education or background.

Why is readability important?

Readability is essential for effective communication, which is the act of ensuring the end reader understands the message you are trying to get across. If a text is challenging to read, a user may lose interest, misunderstand the message or simply give up trying to understand it.

The flip side of this is if a text is easy to read, a reader is more likely to engage with it and understand the message. Readability can also impact SEO as search engines favour content that is considered easier to read. This factor underlines the importance of ensuring that written content is easily readable and accessible to a wide range of audiences.

How to check readability using a checker?

One method to ensure your content is readable is to use a readability checker like ours which will analyze the text and assign it several readability statistics based on various formulas. This will help you have a more in-depth understanding of what rough educational grade a reader would need to be to understand the content.

What our tool checks for

The Flesch-Kincaid Reading Ease formula is designed to assess the readability of a text by examining the average sentence length and syllables per word. Higher scores indicate easier to read text, This formula is a very popular tool for evaluate content accessibility. 

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

Where RE is Reading Ease, ASL is the average sentence length, and ASW is the average number of syllables per word.

An extension of the reading ease formula. The grade level translates the reading ease score to the equivalent U.S. school grade level. This enables authors to gauge the complexity of their writing for a specific audience, ensuring clear communication.

GL = (0.39 x ASL) + (11.8 x ASW) – 15.59

Where GL is Grade Level, ASL is the average sentence length, and ASW is the average number of syllables per word.

The Gunning Fog Index is a readability metric that accounts for sentence length and the number of complex words, which are defined as words with three or more syllables. A higher score indicates a more difficult text.

GFI = 0.4 x (ASL + PHW)

Where GFI is Gunning Fog Index, ASL is the average sentence length, and PHW is the percentage of hard words (words with three or more syllables).

The Simplified Measure of Gobbledygook (SMOG) Index estimates the years of education needed to comprehend a text by analyzing the number of polysyllabic words in a sample. It is often used for evaluating the readability of healthcare and legal documents. 

SMOG = 1.043 x √(30 x PDW) + 3.1291

Where SMOG is the SMOG Index and PDW is the number of polysyllabic words per 30 sentences.

This formula assesses text readability by analyzing syllable patterns and word frequency data. 

First get a sample of 100 words.
GL = 0.0778(ASL) + 0.0455(NS) – 2.2029

Where GL is grade level, ASL is average sentence length and NS is number of syllables

The FORCAST Grade level formula measures text readability based on the frequency of single syllable words. 

First get a sample of 150 words.

Where NOSW is the number of one-syllable words, and NTW is the total number of words in the sample.

This formula considered the number of characters per word and sentences per 100 words to estimate the U.S. grade level required to understand a text. It is unique in that it doesnt rely on syllable counts making it an efficient formula.

CLI = (0.0588 x L) – (0.296 x S) – 15.8

Where CLI is the Coleman-Liau Index, L is the average number of characters per 100 words, and S is the average number of sentences per 100 words.

This formula uses characters per word and words per sentence to determine the readability of a text. We convert the results to the U.S. Grade level.

ARI = (4.71 x CHW) + (0.5 x WPS) – 21.43

Where ARI is the Automated Readability Index, CHW is the average number of characters per word, and WPS is the average number of words per sentence.

This formula incorporates sentence length and percentage of difficult words, which are those not found in a pre defined list of 3,000 familiar words.

DC = (0.1579 x PDW) + (0.0496 x ASL)

Where DC is the Dale-Chall Readability Grade, PDW is the percentage of difficult words, and ASL is the average sentence length.

This formula is specifically designed to analyze texts aimed at young readers, typically grades 1 – 3. By looking at sentence length and unfamiliar words we can determine the rough age at which a reader would need to be for the text.

SRG = (ASL + PDW) / 2

Where SRG is the Spache Readability Grade, ASL is the average sentence length, and PDW is the percentage of difficult words.

The Linsear Write Grade formula evaluates text readability by focusing on the number of simple and complex words in a sample of 100 words.

First collect a sample passage of 100 words.
LWG = (SIMW + (COMW x 3)) 

Where LWG is the Linsear Write Grade, SIMW is the number of simple words, COMW is the number of complex words, and NTW is the total number of words in the sample.

How to use our readability test tool

Step 1:

Find some content you would like to enter into the online readability checker. This could be in the form of a URL, a file, or simply copying and pasting some text.

Step 2:

Once you have entered a URL, uploaded a file or entered some text, click the “Analyze” button and let our tool generate a report.

Step 3 – Interpreting highlighting:

Once our readability checker has generated a readability score, it’s time to interpret it. If you hover over any highlighted text, it will inform you of why that piece of text was highlighted and a tip to help improve on that area. E.g. “This word is over 4 syllables consider using a word with less syllables”.

Step 4 – Interpreting scores:

On the right-hand side, you will notice an output. The initial tab will provide you with a general estimate of how readable your content is, this is based on the Flesch-Kinkaid grade and scale. A widely used formula to estimate readability score. Our readability analyzer also calculates other lesser known readability tests to give you a more holistic understanding of the readability of your content.

Step 5 – Text ‘issues’:

In the text issues tab you will find some more information about your text and, upon hovering see some targets that you want to aim for. E.g. You should be aiming for an average word syllable count of less than 1.4 syllables per word.

Step 6:

In the other tabs you will find more useful information about your text and how you can improve it. There is also a KW density checker to evaluate your targets for SEO purposes.


Take the information provided and try to restructure your content to hit your targets. Click “Analyze” again to re-assess your content and continue to improve.

Tips for improving readability

Improving readability can be achieved through various strategies, including:

Using shorter sentences and paragraphs:

Breaking up content into shorter more digestible sentences and paragraphs will make it easier to understand. Long sentences and paragraphs can be overwhelming for reading increasing the likelihood they lose interest in the content.

Avoiding technical jargon and complex vocabulary:

Using technical jargon can push people away from your content, especially if they are new or unfamiliar with the topic. This kind of writing can be a real barrier to entry for new users. Try to use more simple and clear language to keep a reader engaged with the content and retain information.

Breaking up text with headings and subheadings:

Headings and subheadings will help to break up content into more manageable sections. This makes it easier for a reader to quickly scan through the article to locate the information they need. Additionally headings and subheadings give the reader an outline of the content so they know what to expect.

Using active voice instead of passive voice:

Sentences written in active voice are more direct and less confusing than that of passive voice this will help readers to be more interested and engaged in the article.

Varying sentence structure:

Using a mix of long and short sentences can add variety and interest to the writing. Varying the sentence structure can also help emphasize important points and create a more dynamic and engaging writing style.

Writing for your intended audience:

When writing, it’s essential to consider the audience and write in a way that is appropriate and accessible to them. Writing for an adult academic audience, for example, will require a different writing style than when writing for a younger audience. Understanding your intended audience will both help you as the writer, write better content targeted at that audience and in turn make the content more readable and engaging for readers.


To conclude, improving content readability by using a readability checker tool plays a crucial role in effective communication and making text more accessible to a wider audience. A contents readability is influenced by various factors such as sentence structure, word choice and organization of the text. Readability checkers like our tool can help writers and publishers have a deeper understanding of how readable their content is and areas that you can improve. By implementing strategies such as avoiding technical jargon and breaking up text using headings you can improve the readability of your content. Ultimately readability is a key factor to consider when writing new content that you are looking to optimize for SEO.