Countable nouns name separable entities that can be counted as units: book, apple, chair. They admit singular and plural, and they usually combine with numerals, articles and quantifiers that express quantity. They are closely related to Common Nouns and Proper Nouns, because the notion of counting depends on the type of referent.

The singular names a single unit and the plural names several units. In Spanish, the plural is usually formed with -s or -es, depending on the word's ending, and some nouns keep the same form in both numbers. The spelling of the nominal number is also important for Nominal Number.

IdeaIdea	EjemploExample
El plural suele añadirse con s cuando la palabra termina en vocal.The plural is usually added with -s when the word ends with a vowel.	casa → casashouse → houses
El plural suele añadirse con es cuando la palabra termina en consonante.The plural is usually formed with -es when the word ends with a consonant.	lápiz → lápicespencil → pencils
Algunos sustantivos conservan la misma forma en singular y plural.Some nouns keep the same form in singular and plural.	análisis → análisisanalysis → analysis

Countable nouns are used with numerals to express precise quantities. The basic structure is numeral plus noun, and the noun appears plural when the number is greater than one. This rule is the basis for counting objects, people and discrete units.

IdeaIdea	EjemploExample
Un numeral puede preceder a un sustantivo contable para indicar cantidad precisa.A numeral can precede a countable noun to indicate a precise quantity.	tres librosthree books
El sustantivo suele ir en plural con cantidades mayores que uno.The noun is usually plural with quantities greater than one.	dos sillastwo chairs
El conteo exacto también funciona con unidades de tiempo o elementos separados.Exact counting also works with units of time or separate elements.	cinco minutosfive minutes

Countable nouns are usually accompanied by articles and other determiners that indicate number and gender. The definite articles indicate known reference, while the indefinite ones present an unspecified countable unit. This system is connected to Definite Articles and Indefinite Articles.

IdeaIdea	EjemploExample
El artículo definido concuerda con el sustantivo en número y género.The definite article agrees with the noun in number and gender.	los gatosthe cats
El artículo indefinido presenta una unidad contable no específica.The indefinite article presents an unspecified countable unit.	una mesaa table
El determinante también puede señalar una cantidad aproximada o limitada.The determiner can also indicate an approximate or limited quantity.	algunos vasossome glasses

The gender and number of the noun determine the form of the adjectives and many determiners that accompany it. Therefore, a plural noun requires a plural adjective, and a feminine noun requires feminine forms when they exist. This agreement is central to Adjective Agreement.

IdeaIdea	EjemploExample
El adjetivo concuerda en número con un sustantivo contable plural.The adjective agrees in number with a plural countable noun.	perros grandeslarge dogs
El adjetivo concuerda en género con un sustantivo femenino singular.The adjective agrees in gender with a feminine singular noun.	mesa blancawhite table
La concordancia se mantiene cuando el sustantivo cambia de número.Agreement persists when the noun changes number.	libros interesantesinteresting books

Questions of quantity with countable nouns use cuánto in masculine and cuántas in feminine, depending on the noun. Negation and zero quantity express absence with determiners like ningún and ninguna, or with zero plus noun. These resources are useful for Quantitative Adjectives.

IdeaIdea	EjemploExample
Cuántos se usa con sustantivos contables masculinos.Cuánto is used with masculine countable nouns.	¿Cuántos libros hayHow many books are there
Cuántas se usa con sustantivos contables femeninos.Cuántas is used with feminine countable nouns.	¿Cuántas mesas hayHow many tables are there
Ninguna expresa ausencia total con sustantivos femeninos.None expresses total absence with feminine nouns.	ninguna respuestano answer

When a referent is perceived as matter or mass, Spanish usually requires a measure or unit to make it countable. Hence expressions like a bottle of water or a glass of milk appear, where the unit is counted and the content is presented via a measure relation. This behavior is related to Uncountable Nouns.

IdeaIdea	EjemploExample
Una unidad de medida permite contar un contenido no contable directamente.A unit of measure allows counting a non-countable content directly.	una botella de aguaa bottle of water
La unidad puede sustituir al sustantivo de materia en el habla cotidiana.The unit can substitute for the material noun in everyday speech.	un caféa coffee
El cuantificador se aplica a la unidad contable y no a la materia.The quantifier applies to the countable unit and not to the material.	dos vasos de lechetwo glasses of milk

Some nouns change interpretation depending on context and can be countable or function with sense of measure, type or portion. There are also collective nouns that are singular in grammar although they refer to several individuals, as with Collective Nouns. In regional and colloquial use, certain units of measure replace the main name quite naturally.

IdeaIdea	EjemploExample
Un sustantivo puede señalar tipos distintos cuando aparece en plural.A noun can indicate distinct types when it appears in plural.	dos vinostwo wines
Un colectivo funciona como singular aunque represente varios seres.A collective noun functions as singular even when it represents several beings.	el equipo ganathe team wins
El uso coloquial puede preferir una unidad de medida breve.Colloquial use may prefer a brief unit of measure.	un caféa coffee

Counting in Spanish depends on the combination between number, determiners, agreement and choice between countable and uncountable nouns. Plural forms, quantity questions and expressions of absence show how a noun organizes quantitative information in the sentence. This system prepares the study of Nominal Diminutives, where the nominal form can also express value, size or proximity.