Readability score calculator
Score text with Flesch reading ease, Flesch–Kincaid, Gunning fog, SMOG, Coleman–Liau and ARI.
A clear answer. Here’s how.
Counts words, sentences, letters and estimated syllables, then applies the published formulas: Flesch reading ease 206.835 − 1.015(words ÷ sentences) − 84.6(syllables ÷ words); Flesch–Kincaid grade 0.39(words ÷ sentences) + 11.8(syllables ÷ words) − 15.59; Gunning fog 0.4[(words ÷ sentences) + 100(3+ syllable words ÷ words)]; SMOG 1.043√(3+ syllable words × 30 ÷ sentences) + 3.1291; Coleman–Liau 0.0588L − 0.296S − 15.8; ARI 4.71(letters ÷ words) + 0.5(words ÷ sentences) − 21.43.
See a worked example
Worked example
A fixed demonstration, separate from the values you enter above.
- Text to score
- Plain language helps people understand quickly. Short sentences are easier to follow. Long, winding sentences full of unfamiliar terminology often exhaust readers before they reach the point.
Example result
- Words
- 27
- Sentences
- 3
- Syllables (estimated)
- 50
- Words with 3+ syllables
- 5
- Flesch reading ease
- 41.03
- Reading ease band
- Difficult (college)
- Flesch–Kincaid grade
- 9.77
- Gunning fog index
- 11.01
- SMOG index
- 10.5
- Coleman–Liau index
- 15.97
- Automated readability index
- 11.16
- Average of the five grade levels
- 11.68
US school-grade scales; ease runs from 0 (hard) to about 100. Syllables are counted by an English heuristic that is usually within a few percent, and sentences end at . ! or ?, so abbreviations such as “Dr.” add a sentence. SMOG is designed for 30+ sentences and is rough for short texts. Formulas measure sentence and word length, not meaning, structure or tone.