Cardinal Numbers in Spanish

Overview

Numbers are among the first things you learn in any language, and for good reason -- you need them for telling time, shopping, giving your phone number, and counting just about anything. Spanish cardinal numbers from 0 to 100 follow predictable patterns, but they also have a few quirks that make them uniquely Spanish, such as single-word forms for numbers 16 through 29 and gender agreement for the number one.

At the CEFR A1 level, getting comfortable with these numbers opens up a huge range of practical situations. Once you can count confidently, you will find that many everyday interactions -- ordering food, understanding prices, exchanging contact information -- become much smoother.

How It Works

Numbers 0-15

These must be memorized individually:

Number	Spanish	Number	Spanish
0	cero	8	ocho
1	uno	9	nueve
2	dos	10	diez
3	tres	11	once
4	cuatro	12	doce
5	cinco	13	trece
6	seis	14	catorce
7	siete	15	quince

Numbers 16-29 (single words)

Numbers 16-19 and 21-29 are written as single words:

Number	Spanish	Number	Spanish
16	dieciséis	21	veintiuno
17	diecisiete	22	veintidós
18	dieciocho	23	veintitrés
19	diecinueve	24	veinticuatro
20	veinte	25	veinticinco

And so on through veintinueve (29).

Numbers 30-99

From 30 onward, numbers are written as separate words joined by y (and):

Number	Spanish
30	treinta
31	treinta y uno
40	cuarenta
42	cuarenta y dos
50	cincuenta
60	sesenta
70	setenta
80	ochenta
90	noventa
99	noventa y nueve

The number 100

Form	When to use	Example
cien	before a noun or alone	cien euros, cien personas
ciento	in compound numbers	ciento uno (101), ciento veinte (120)

Gender agreement with uno

The number uno changes form before a noun:

Form	Context	Example
un	before masculine nouns	un libro (one book)
una	before feminine nouns	una mesa (one table)
veintiún	compound, before masculine nouns	veintiún años (twenty-one years)
veintiuna	compound, before feminine nouns	veintiuna personas (twenty-one people)

Examples in Context

Spanish	English	Note
Uno, dos, tres.	One, two, three.	basic counting
Tengo veintiún años.	I'm twenty-one years old.	un before masculine noun
Cuesta treinta y dos euros.	It costs thirty-two euros.	compound number with y
Cien euros, por favor.	One hundred euros, please.	cien before noun
Mi número es el quince.	My number is fifteen.	standalone number
Hay dieciséis estudiantes.	There are sixteen students.	single-word form
Son cuarenta y cinco minutos.	It's forty-five minutes.	compound number
Página noventa y nueve.	Page ninety-nine.	compound number
Necesito ciento veinte gramos.	I need one hundred twenty grams.	ciento in compounds
Dame dos kilos.	Give me two kilos.	simple number

Common Mistakes

Using ciento before a noun

• Wrong: Ciento euros.
• Right: Cien euros.
• Why: Use cien when the number stands alone or directly before a noun. Use ciento only in compound numbers like ciento uno or ciento cincuenta.

Forgetting to shorten uno before masculine nouns

• Wrong: Tengo uno hermano.
• Right: Tengo un hermano.
• Why: Before a masculine noun, uno shortens to un. This also applies to compounds: veintiún libros, not veintiuno libros.

Writing 16-29 as two words

• Wrong: diez y seis
• Right: dieciséis
• Why: Numbers 16-19 and 21-29 are always written as single words in modern Spanish. The old two-word forms are archaic.

Practice Tips

• Count everything. Count steps as you walk, count items at the grocery store, count cars on the street. Repetition with real objects makes numbers stick.

• Practice in groups of ten. Master 0-10 first, then 11-20, then the tens (30, 40, 50...). Once the tens are solid, filling in the gaps (31, 32, 33...) is easy because the pattern is consistent.

• Use numbers in context. Practice saying prices (cuesta quince euros), ages (tengo veinticinco años), and times (son las tres y cuarto). Numbers in real phrases are easier to remember than numbers in isolation.

Related Concepts

• Next steps: Ordinal Numbers -- Learn to say "first," "second," "third"
• Next steps: Time & Dates -- Apply numbers to tell time and express dates