Readability Score Calculator Online Free — Flesch-Kincaid
Calculate Flesch Reading Ease score and grade level.
Flesch Reading Ease formula: 206.835 − (1.015 × avg sentence length) − (84.6 × avg syllables/word). Higher scores = easier to read. Score 60–70 is standard for general audiences.
What is Readability Score?
Calculates the Flesch Reading Ease score (0–100) and Flesch-Kincaid Grade Level for your text. The Reading Ease score tells you how easy your text is to read; the Grade Level tells you the US school grade needed to understand it.
Common Use Cases
Checking blog post readability for your target audience, ensuring legal documents are accessible, academic writing assessment, SEO content optimisation, and educational content grading.
How It Works
Flesch Reading Ease = 206.835 − (1.015 × avg sentence length) − (84.6 × avg syllables per word). Grade Level = 0.39 × ASL + 11.8 × ASW − 15.59. Syllables are estimated using English vowel-cluster heuristics.
Frequently Asked Questions
What is the ideal Flesch Reading Ease score?
Aim for 60–70 for general audience content (roughly Grade 8–9 reading level). Academic writing typically scores 30–50; children's books score 80–100.
How accurate is the syllable count?
The syllable counter uses heuristic rules and is ~90% accurate on standard English text. Unusual words or proper nouns may be slightly off.
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