Cuál es la diferencia entre cualquiera y quienquiera?

Cuál es más común?

Question

Cuál es la diferencia entre cualquiera y quienquiera?

Cuál es más común?

Ssnot · Answer

Cualquiera = Anyone
Quienquiera = Whoever wants

Talking about things you can just use "cualquiera", but talking about people you can use both of them, for example:

- ¿Cuál carro quieres?, Cualquiera
Which car do you want?, Anyone

- Puede venir cualquiera
- Puede venir quienquiera
Anyone can come
Whoever wants can come

I'd say that both are equally used, none of them is more or less used to be honest.

Dann_01 · Answer

@Jackson_Bain
[Edited] 
To use "cualquiera" or ["quien quiera"] . 
"cualquiera" for things [or people] and ["quien quiera" ][only] for persons, generally. There is a big difference, first word is used when you're who has to choose 'something', the second word is used when you leave the decision to 'someone' else, I mean the decision is not up to you alone.

For example :
1. Which do you prefer, pizza or hamburger?

-cualquiera de las dos.

2.Who on our team will give the speech.?

-[Quien quiera.] 
("Whoever wants to do it.")

A "exception" of use for "cualquiera":

1.Who do you prefer, Bach or Mozart? 
-Cualquiera de los dos, me gusta oír a Bach cuando estudio pero también escucho a Mozart.

(note that even though you're talking about people, your decision doesn't mean someone else has to do something.)
 
[added :
2. Oh sorry I'm wrong! 
-No te preocupes, a cualquiera le puede pasar.]

I hope this help you.

HanyuuFurude · Answer

"Quienquiera" means "cualquiera" and it has to be used with "que". It's normally used in phrases like "quienquiera que fuese" or "quienquiera que sea", meaning "whoever it/that is". The answers the other people gave would make sense for "quien quiera" but that's completely different from "quienquiera".

Dann_01 · Answer

@Jackson_Bain
Sorry, I had to edit my previous answer. I honestly think I hadn't understood your question correctly. I agree with @HanyuuFurude ,  my answer is focused on "quien quiera" and not on "quienquiera". I think his explanation is more appropriate except  on that "quienquiera"/"cualquiera"  'it has to be' with "que", I'd be more cautious about that.

In the reference :

https://dle.rae.es/quienquiera?m=form

Shows for example 
**"A quienquiera le puede pasar."

Or in my example, "No te preocupes, a cualquiera le puede pasar."

In none is it necessary to add "que".

Now, to back to you second cuestion "Which is more common?" 
Really I think they are used with the same frequency but in different situations, for example in (**) the truth is that I've never heard it like that, using "quienquiera". 
On the example of my previous message:
"-Cualquiera de los dos, me gusta oír a Bach cuando estudio pero también escucho a Mozart. "

In an answer like this is better "cualquiera", I advise you never to use "Quienquiera" this to avoid confusion with 
"quien quiera".

On other hand, also I think that the  phrases with the format mentioned by @HanyuuFurude also are commons, using "quienquiera que... ", but remember that context is important.

I hope this help you.

Cuál es la diferencia entre cualquiera y quienquiera? Cuál es más común? See a translation

Cuál es la diferencia entre cualquiera y quienquiera?

Cuál es más común?