Readability Scoring Tools

Last updated on Dec 20, 2023

From syllabi, to assignment instructions, to assessment and feedback, written text plays a crucial role in student understanding of course materials and expectations. Readability scoring tools are a great way to make sure you’re using accessible language to support the academic success of multilingual students. These tools analyze text based on a variety of criteria, such as sentence and word length, syllables, grammar, and word complexity. They can provide an overall difficulty score and also highlight specific words that may be more challenging. This can help you catch academic or discipline-specific vocabulary that requires more explanation because students are not familiar with it. While these scoring systems are not infallible, they provide useful guidelines and highlight areas of concern.

One of the most popular scoring systems is Flesch-Kincaid Grade Level, which assesses the difficulty of a text based on sentence complexity, word choice, and coherence. A text is then assigned a US school grade level; the lower the grade level, the easier the text is to understand. There are many online readability scoring tools to choose from. This curated list will help guide you as you explore and discover how useful these tools can be.

General readability scoring tools

Language proficiency focused tools

Readability Formulas

This free, online tool allows you to copy/paste up to 3500 words of text or upload a .txt, .pdf, or .docx file to be analyzed. It also has a robust articles section to provide more background information on readability scoring in general and specific readability formulas, as well as a guide on writing for college student readers.

To use this tool:

Upload or copy/paste your text.

Image of the Readability Formula home screen with text pasted into the text editor box

2. You can choose Flesch-Kincaid Grade Level, experiment with other readability scoring formulas, or run multiple formulas at once. Once you’ve chosen a formula, click Calculate Text Readability.

List of the Readability Formula choices, with Flesch-Kincaid Grade level highlighted

3. Your text will receive a score showing the difficulty level, grade level, and recommended age range. You can drill down into more advanced features by clicking the green Show word stats button.

Flesch-Kincaid grade level result for a text that was marked as Extremely Difficult. The Show Word Stats button for advanced features is highlighted

Visualization Tools

The Word Stats section has two helpful visualization tools:

1. Sentence Visualizer

View and highlight parts of the text based on sentence type and length.

Image of Readability Formula's Sentence Visualizer feature, showing long sentences highlighted in yellow

2. Words/Syllables Visualizer

View and highlight words based on syllable, complexity, and more.
Particularly useful for identifying the most difficult words in the text.

Image of Readability Formula's Words/Syllables Visualizer with challenging words bolded

Readability Analyzer

Readability Analyzer is another free online tool that allows you to upload or copy/paste text to be analyzed. Compared to Readability Formulas, it has fewer formulas and fewer details about what goes into scoring. However, it has two other unique features that can be helpful: Paragraph Readability and Difficult and Extraneous Word Finder.

To use this tool:

Upload or copy/paste your text and then click Analyze.

Image of Readability Analyzer's text box with sample text copy/pasted. The Analyze button is highlighted

2. Readability Analyzer automatically analyzes the text and provides scores for 6 different popular formulas. It also provides passage statistics, including the percentage of difficult words that were used.

Image of Readability Analyzer's results page, showing word statistics and scoring based on different formulas

Special Features

1. Paragraph Level Readability

Looks at readability on a paragraph by paragraph level.
Explains why certain paragraphs may have different ratings, so you can compare and contrast.

Image of Readability Analyzer's paragraph level readability page

2. Difficult and Extraneous Word Finder

Can identify rare words and complex words
Allows you to download .txt file vocabulary lists
Clicking on a word provides a definition you could share with students

Image of where to find the Difficult and Extraneous Word Finder under the Other Readability Tools tab

Image of Difficult and Extraneous Word Finder results showing rare words. The rare words and long words tabs are highlighted

There are also readability tools that evaluate text based on CEFR (Common European Framework of Reference), which is an international language proficiency standard.

CEFR has 6 levels to describe a person’s language proficiency:

C2 (high)	Can function at the ability level of a native speaker
C1	Can understand a wide variety of complex texts and use language flexibly and effectively
B2	Can hold longer conversations, understand the key points of complex texts, and function well in an English-speaking environment
B1	Can hold limited conversations and understand the key points of less complex text
A2	Can use and understand simple sentences
A1 (low)	Can use and understand basic phrases and everyday expressions

The following tools can analyze text to assess the language proficiency level needed to understand it. This information can help you tailor your assignment instructions, readings, and other course materials to align with student needs and linguistic abilities.

CEFRlevels Text Analyzer

Evaluates text based on CEFR levels. It will also generate a vocabulary list of the more difficult words and allow you to generate definitions with the click of a button.

Image of CEFR levels results screen, highlighting the generated words list and where to click to generate definitions

Lexical Complexity Analysis with EFLLex

Analyzes text and generates a filterable, color-coded word cloud of terms by CEFR level.