Qué vs cuál in Spanish: which question word

Both can translate as “what” or “which”, but they ask different things. Use qué to ask for a definition or an explanation, and directly before a noun. Use cuál (plural cuáles) to pick one or more items out of a set. A quick test: if you could answer with “it’s the kind of thing that…”, use qué; if you would point at a choice, use cuál.

Qué asks “what is it?”

Use qué when you want something defined, identified or explained.

¿Qué es la fotosíntesis?
What is photosynthesis?

¿Qué quieres comer?
What do you want to eat?

Always use qué, never cuál, immediately before a noun.

¿Qué color te gusta?
What color do you like?

Cuál asks “which one?”

Use cuál when you choose from a group, whether or not the group is named.

Hay tres opciones. ¿Cuál prefieres?
There are three options. Which do you prefer?

¿Cuáles son tus libros favoritos?
Which are your favorite books?

The tricky one: cuál before “es” + a fact

Here Spanish differs from English. When you ask for a specific piece of information like a name, number or date, Spanish uses cuál es, not qué es, because it treats it as choosing from many possible answers.

¿Cuál es tu nombre?
What is your name?

¿Cuál es tu número de teléfono?
What is your phone number?

You only switch to qué es when you genuinely want a definition: ¿Qué es un nombre? means “What is a name?” (explain the concept).

Common mistakes

Using cuál before a noun

Before a noun, Spanish prefers qué, even when English says “which”.

¿Cuál libro quieres? → ¿Qué libro quieres?
Which book do you want?

Using qué es for personal information

For a name, age or number, Spanish asks cuál es.

¿Qué es tu apellido? → ¿Cuál es tu apellido?
What is your last name?

Forgetting the accent in questions

Question words carry a written accent: qué, cuál. Without it, que and cual are relative words (“that”, “which”) in a statement.

¿Que quieres? → ¿Qué quieres?
What do you want?

The accented-versus-plain split here is the same one you sort out with tú and tu in possessives, and a clear question word sets up agreement-free answers like the ones in también vs tampoco. In Fluera you build and answer short questions, so choosing qué or cuál happens in real exchanges. Use that when you practice Spanish and the cuál es tu nombre pattern stops feeling backwards.

Practice