What Is the Automated Readability Index?

The Automated Readability Index (ARI) is another readability test for text in the English language to measure readability of your content. It is designed to measure how easy your text is to read and understand.

Using a similar formula as other popular readability tools like Flesch Reading Ease, the ARI score gives you an estimate of the U.S. school grade level necessary to clearly read and understand a passage of text.

As a readability index tabulator, ARI focuses on the average number of characters per word, making it straightforward and easy to apply. This method assesses word difficulty by determining the number of characters in a word, as longer words often correlate with increased difficulty in reading comprehension. It also considers sentence difficulty (number of words per sentence).

The ARI is crucial in assessing adult reading material in military use, ensuring that documents meet the comprehension needs of diverse adult readers. Avoiding excessive technical jargon in these documents is essential to ensure clarity and comprehension.

What Is the ARI Readability Calculator?

The ARI readability calculator uses the automated readability index formula to calculate the readability of a text. It also calculates the readability of a text in terms of U.S. school grade levels.

To use the ARI readability calculator, simply upload or paste your content into the text input box above. The ARI score will then be shown immediately. You can then edit your text to make sure your writing resonates with the intended audience.

Note: You should make sure your text is spell-checked and properly punctuated beforehand. A clean, properly formatted, and grammatically correct text will reduce errors and yield the best results.

How to Calculate the Automated Readability Index Score

The ARI formula is based on the average number of characters per word (AWL) and the average number of words per sentence (ASL). Characters include any letters, numbers, symbols, etc. White spaces between characters are not counted.

4.71 × (characters ÷ words) + 0.5 × (words ÷ sentences) - 21.43

This formula shows that lower ARI scores indicate that the text is easier to read.

Here are the interpreted ARI readability scores:

How Can You Increase Your ARI Score?

For a better ARI score, you should aim to use shorter words and sentences. Reducing the average number of characters per word and keeping sentences shorter will help make your text more readable. To increase your ARI score, you should use longer words and sentences.

Limitations of the ARI Formula

While readability scores can provide a useful indication of a text's readability, they have limitations. The ARI method does not consider how variations in sentence length affect reading difficulty or how difficult words may be within a text. It also does not take into account the difficulty of the subject matter and linguistic factors, such as sentence structure, vocabulary diversity, and syntax complexity. Individual reading skill and cultural differences are also overlooked. To get a better evaluation of the readability of a text or a readability score, you should experiment with other readability tests.