This tool scores how easy a Portuguese passage is to read using the Martins et al. (1996) adaptation of the Flesch Reading Ease formula. It measures two things that drive difficulty: how long the sentences are and how many syllables the average word carries.
How it works
The adapted formula keeps the original Flesch coefficients but raises the base constant for Portuguese:
ease = 248.835 - 1.015 × (words / sentences) - 84.6 × (syllables / words)The tool counts words, splits sentences on ., ?, !, and …, and counts
syllables with real Portuguese diphthong and hiatus rules. Longer sentences and
more polysyllabic words both pull the score down, so concise sentences and
shorter words raise it. Higher scores mean easier text.
Why the constant changes
The English Flesch formula uses a base constant of 206.835. Portuguese carries more syllables per word on average — morphologically, Portuguese words tend to be longer due to inflections, prepositions contracted with articles (do, da, ao, na), and verb endings. Martins and colleagues measured this systematically and recalibrated the base term to 248.835 so that the resulting scale aligns with reader-perceived difficulty in Brazilian Portuguese, rather than artificially penalising the language.
Score bands and what they mean
| Score | Band label | Typical audience |
|---|---|---|
| 75–100 | Muito fácil (very easy) | Children, simple consumer text |
| 50–75 | Fácil (easy) | General adult readers |
| 25–50 | Difícil (difficult) | Educated adults, technical readers |
| 0–25 | Muito difícil (very difficult) | Academic, legal, specialist text |
Worked example
Consider this short Brazilian news sentence:
O governo federal anunciou nesta terça-feira um pacote de medidas econômicas destinadas a reduzir a inflação.
- Words: 18
- Sentences: 1
- Syllables: approximately 56 (average ~3.1 per word)
- Words per sentence: 18
ease = 248.835 − 1.015 × 18 − 84.6 × 3.1 ≈ 248.835 − 18.27 − 262.26 ≈ −31.7
A very negative score reflects the formal register, technical vocabulary (medidas econômicas, reduzir a inflação), and a compound noun-heavy structure typical of official news text. For general-audience writing, aim for scores above 50.
How to improve a low score
The two levers are sentence length and word length. In practice:
- Break long sentences at conjunctions or with a full stop. A single reform of splitting one 30-word sentence into two 15-word sentences can add 5–10 points.
- Prefer shorter synonyms where precision allows: usar instead of utilizar, mas instead of entretanto, agora instead of neste momento.
- Reduce embedded clauses: relative clauses (que…) add words and syllables simultaneously.
- Watch nominalisation: converting verbs to nouns (a realização de) typically adds two syllables and reduces direct action.
Re-paste after editing to see the improvement quantified.
Caveat on European Portuguese
The Martins et al. calibration used Brazilian Portuguese texts. European Portuguese has the same orthographic syllable structure, so the formula gives a sound relative ranking and can be used for comparison — but treat the absolute band label as approximate rather than precisely calibrated for a Lisbon newspaper or Portuguese academic text.