Most Brazilian Portuguese comparatives are built analytically with mais — mais alto, mais caro (see the regular forms page). But four very common adjectives have single-word irregular comparatives that you must never combine with mais. Saying mais bom is as wrong as saying more good in English. This page covers all four, plus the two related adverbs, and explains the one place where mais grande is occasionally tolerated.
The four irregular adjectives
These mirror English almost exactly — good → better, bad → worse — which makes them easier to remember than they look.
| Adjective | Meaning | Comparative | English |
|---|---|---|---|
| bom | good | melhor | better |
| ruim / mau | bad | pior | worse |
| grande | big | maior | bigger |
| pequeno | small | menor | smaller |
Each is a single word that already contains the comparative meaning. You add (do) que after it just like a regular comparative, but you never put mais in front.
Esse restaurante é melhor do que o outro.
This restaurant is better than the other one.
O trânsito hoje está pior que ontem.
The traffic today is worse than yesterday.
São Paulo é maior do que o Rio.
São Paulo is bigger than Rio.
Meu apartamento é menor que o seu.
My apartment is smaller than yours.
bom → melhor (never "mais bom")
Bom (good) and its feminine boa both become melhor in the comparative. Melhor is invariable in gender (one form for masculine and feminine) and pluralizes to melhores.
A comida da minha avó é melhor do que a de qualquer restaurante.
My grandmother's food is better than that of any restaurant.
Essas são as melhores notas da turma.
These are the best grades in the class.
There is a narrow exception: when bom means morally good or kind (a character judgment) rather than "of higher quality," some speakers say mais bom — but this is colloquial and many consider it nonstandard. In writing, prefer melhor or rephrase (mais bondoso, mais gentil).
ruim / mau → pior (never "mais ruim" in careful speech)
Both ruim and mau (bad) become pior. Pior is invariable in gender and pluralizes to piores.
Esse remédio é pior que a doença.
This medicine is worse than the disease.
Os piores dias já passaram.
The worst days are already behind us.
You will hear mais ruim in casual Brazilian speech (it is genuinely common in informal registers), but it is considered substandard and should be avoided in writing or formal settings. Pior is always safe.
grande → maior, pequeno → menor
Maior (bigger) and menor (smaller) are invariable in gender and pluralize to maiores and menores.
O novo estádio é maior do que o antigo.
The new stadium is bigger than the old one.
Quero um quarto menor, esse é grande demais.
I want a smaller room, this one is too big.
As cidades maiores têm mais opções de transporte.
The bigger cities have more transport options.
When is "mais grande / mais pequeno" allowed?
This is the honest, nuanced part — and the answer differs between Brazil and Portugal.
- In Brazil, maior and menor are the standard comparatives for size, and mais pequeno is essentially not used. Mais grande is wrong in ordinary size comparison.
- In European Portuguese, mais pequeno is perfectly normal and even preferred over menor in many contexts. A Brazilian learner reading a Portuguese text will encounter mais pequeno and should recognize it, but should not produce it.
- Mais grande survives only in a few fixed or emphatic expressions and in the absolute superlative idea (and even there grandíssimo / maior dominate). Treat mais grande as wrong for size.
The adverbs: bem → melhor, mal → pior
The adverbs bem (well) and mal (badly) also have irregular comparatives, and they happen to be identical to the adjective comparatives: melhor and pior. Context tells you whether melhor is functioning as an adjective ("better") or an adverb ("better / well").
Ela canta melhor do que eu.
She sings better than I do.
Depois do remédio, ele dormiu melhor.
After the medicine, he slept better.
O time jogou pior do que na semana passada.
The team played worse than last week.
Note the difference from English, where the adjective (better) and the adverb (better) also coincide — so this one feels natural to English speakers. The Portuguese trap is the opposite: don't write mais bem / mais mal for the everyday sense. (Mais bem does exist before past participles — mais bem preparado — but that is a separate, advanced structure.)
Comparison with English
The parallel with English is striking and helpful:
| English | Portuguese |
|---|---|
| good → better (not "more good") | bom → melhor (not "mais bom") |
| bad → worse (not "more bad") | ruim/mau → pior (not "mais ruim") |
| big → bigger | grande → maior |
| small → smaller | pequeno → menor |
Because English speakers already know not to say more good, the instinct transfers perfectly to melhor and pior. The two that need extra attention are maior and menor — English speakers, used to building mais + adjective for everything else, sometimes overgeneralize and produce mais grande. Resist it.
Common Mistakes
❌ Essa pizza é mais boa do que a outra.
Incorrect — 'bom' has no analytic comparative; use 'melhor'.
✅ Essa pizza é melhor do que a outra.
This pizza is better than the other one.
❌ O trânsito hoje está mais ruim que ontem.
Substandard — use 'pior' in careful speech and writing.
✅ O trânsito hoje está pior que ontem.
The traffic today is worse than yesterday.
❌ São Paulo é mais grande do que o Rio.
Incorrect in Brazil — use 'maior'.
✅ São Paulo é maior do que o Rio.
São Paulo is bigger than Rio.
❌ Meu quarto é mais pequeno que o seu.
Portugal usage, not Brazilian — use 'menor'.
✅ Meu quarto é menor que o seu.
My room is smaller than yours.
❌ Ela canta mais bem do que eu.
Incorrect — the adverb 'bem' becomes 'melhor'.
✅ Ela canta melhor do que eu.
She sings better than I do.
Key Takeaways
- Four irregulars: bom→melhor, ruim/mau→pior, grande→maior, pequeno→menor.
- Never add mais to these — they already carry the comparative meaning.
- In Brazil, size is maior/menor; mais pequeno is Portugal usage and mais grande is wrong.
- The adverbs bem→melhor and mal→pior match these forms exactly.
Now practice Portuguese
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Start learning Portuguese→Related Topics
- Comparative: Regular FormsA2 — How to build regular comparatives in Brazilian Portuguese — superiority with mais...(do) que, inferiority with menos...(do) que, and equality with tão...quanto/como.
- Relative Superlative (O Mais ... De)A2 — The Brazilian Portuguese relative superlative — definite article + mais/menos + adjective + DE + a set — picks out the most or least of a group, with irregulars like o melhor and o pior.
- Common Mistakes: OverviewA2 — A map of the errors Brazilian Portuguese learners actually make, sorted by first language — because English speakers and Spanish speakers trip over completely different things.
- Adjectives: OverviewA1 — How Brazilian Portuguese adjectives work — they agree with the noun in gender and number and usually follow it, the mirror image of English's invariable pre-nominal adjective.