Flesch-Kincaid is a readability formula that scores text based on sentence length and syllable count, producing both a 0-100 ease score and a US grade-level equivalent. It is built into most SEO plugins, but it measures readability, not ranking potential directly.
How the Score Is Calculated
The Flesch Reading Ease formula weighs average sentence length and average syllables per word – shorter sentences and simpler words produce a higher, easier-to-read score. The Flesch-Kincaid Grade Level version converts the same inputs into an equivalent US school grade, so a score of 8 means the text is readable at an eighth-grade level.
What a Good Score Looks Like
| Reading ease score | Difficulty | Typical use |
|---|---|---|
| 90-100 | Very easy | Simple consumer content |
| 60-70 | Standard | Most blog content and web copy |
| 30-50 | Difficult | Technical or academic content |
| 0-30 | Very difficult | Legal or highly specialised writing |
Does It Actually Affect SEO?
Readability is not a confirmed direct Google ranking factor, but it correlates strongly with user engagement metrics – time on page, bounce rate – which do influence how search engines judge content quality indirectly. Writing for a general audience at a 60-70 ease score is a reasonable default for most web content, technical SEO or B2B writing included.
Frequently asked questions
Is Flesch-Kincaid a Google ranking factor?
Not directly confirmed as one, but readable content tends to perform better on engagement metrics that indirectly support rankings.
What Flesch-Kincaid score should I aim for on a blog?
A reading ease score of 60 to 70 works well for most general-audience blog content, roughly an eighth to ninth-grade reading level.
Does a low readability score mean the writing is bad?
Not necessarily. Technical, legal, or academic content naturally scores lower and that can be appropriate for the audience – the score should match audience expectations, not chase a universal target.
Serpwize writes for both readability and search intent on every content deliverable. See our SEO outsourcing service.