Cardinal Numbers in Portuguese

Overview

Cardinal Numbers (Números Cardinais) is a beginner (CEFR A1) topic in Portuguese grammar. Cardinal numbers 0-100. Um/uma agrees in gender. Numbers 16-19 can be written as one word (dezasseis). Cem (100) vs cento (101+).

Understanding cardinal numbers is essential for building correct Portuguese sentences and communicating effectively. This concept is introduced at the A1 level and forms part of the foundation for more advanced grammar structures.

Whether you are learning Brazilian or European Portuguese, mastering cardinal numbers will significantly improve your ability to express yourself naturally and accurately in a variety of contexts.

How It Works

Numbers 0-20:

Number	Portuguese	Number	Portuguese
0	zero	11	onze
1	um/uma	12	doze
2	dois/duas	13	treze
3	tres	14	catorze
4	quatro	15	quinze
5	cinco	16	dezasseis
6	seis	17	dezassete
7	sete	18	dezoito
8	oito	19	dezanove
9	nove	20	vinte
10	dez

Tens: vinte (20), trinta (30), quarenta (40), cinquenta (50), sessenta (60), setenta (70), oitenta (80), noventa (90).

Use e between tens and units: vinte e um (21). Cem (100 alone) vs cento (101+): cento e vinte (120). Gender: um/uma, dois/duas.

Examples in Context

Portuguese	English	Note
um, dois, três	one, two, three
vinte e um	twenty-one
trinta e dois	thirty-two
cem euros	one hundred euros
uma cerveja	one beer	feminine
dois cafes	two coffees	masculine
duas cervejas	two beers	feminine
cento e cinquenta	150	cento
quarenta e quatro	44

Common Mistakes

Incorrect form usage

• Wrong: Applying rules from English or other languages directly
• Right: Follow Portuguese-specific patterns for cardinal numbers
• Why: Portuguese has its own rules that do not always align with English or other Romance languages.

Forgetting agreement rules

• Wrong: Not matching gender, number, or person correctly
• Right: Ensure all elements in the sentence agree with each other
• Why: Portuguese requires strict agreement between subjects, verbs, articles, adjectives, and pronouns.

Mixing formal and informal registers

• Wrong: Using tu forms with voce verb conjugations, or vice versa
• Right: Be consistent with your chosen register throughout a conversation
• Why: Register consistency is important for natural-sounding Portuguese.

Usage Notes

This concept appears across both Brazilian and European Portuguese, though specific usage patterns may differ between the two variants. At the A1 level, focus on understanding the core patterns before worrying about regional differences.

In everyday conversation, cardinal numbers is used frequently in both formal and informal contexts. Pay attention to how native speakers use it in the media you consume, and note any differences between Brazilian and Portuguese sources.

Practice Tips

1. Practice cardinal numbers with authentic Portuguese texts, listening for how native speakers use these forms in context.
2. Create flashcards with complete example sentences rather than isolated words to reinforce natural patterns.
3. Write short paragraphs using cardinal numbers and compare them with native-written texts to identify areas for improvement.

Related Concepts

• Next steps: Ordinal Numbers -- builds on cardinal numbers concepts
• Next steps: Time & Dates -- builds on cardinal numbers concepts