Flesch Reading Ease
0 (hardest) → 100 (easiest)
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Hard
Standard
Easy
Consensus reading grade
Average of FK · Fog · SMOG · ARI · CLI
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grade
Not enough text to score reliably (need ~30 words)
Grade-level breakdown
Each formula reports a US school grade level
Flesch-Kincaid
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Vocabulary + sentence length, syllable-based
Gunning Fog
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Penalises 3+ syllable words; aim ≤ 12 for general audience
SMOG
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Robust on ~30-sentence samples; common in healthcare
Automated RI
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Character-based; no syllable counting needed
Coleman-Liau
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Character-based; widely used in education research
Readability formulas need at least ~30 words and one full sentence to be meaningful.