Free Readability Score Checker
Get a Flesch reading-ease score, grade level, and difficulty rating for your text.
What is a readability score?
A readability score measures how easy or difficult a piece of text is to read. ProseTool uses the Flesch-Kincaid formula — the most widely used readability metric — to produce a score from 0 to 100 and an equivalent school grade level.
Higher scores mean easier reading. A score of 60–70 corresponds to plain English suitable for most adults. Academic and legal writing often scores below 30.
The Flesch-Kincaid formula explained
The score is based on two factors: average sentence length (shorter is easier) and average word length in syllables (shorter words are easier). The formula: 206.835 − (1.015 × words/sentences) − (84.6 × syllables/words).
What score should I aim for?
Blog posts and web content: 60–70
Aim for plain, conversational language. Short paragraphs, short sentences, and common vocabulary keep readers engaged.
Business emails: 60–75
Emails should be direct and easy to scan. Below 50 may feel dense or overly formal.
Academic writing: 30–50
Academic prose is inherently more complex. The goal isn't simplicity but precision and clarity at an appropriate level.
Frequently asked questions
How do I improve my readability score?
Break long sentences into shorter ones. Replace multi-syllable words with simpler alternatives. Use active voice. Aim for one idea per sentence.
What is a good readability score for SEO?
Google doesn't use readability as a direct ranking factor, but readable content keeps users on the page longer. Aim for a score of 60+ for most web content.
Does readability score apply to all languages?
The Flesch-Kincaid formula was designed for English. Scores for other languages will be calculated but may not be accurate.
What score should a blog post have?
Most blogs aim for 60–70 (Grade 7–8 equivalent). This is plain English accessible to most adult readers without being condescending.