What is the difference between what and which?

For example, what is the difference between the following sentences?

What is correct?

Which is correct?

4 Answers 4


Which and what have different meanings. Which is used in questions to ask somebody to be exact about one or more people or things from a limited number.

For example, you ask What name do you prefer for your son? because there are many possible names to give to a baby.
Suppose that you're instead talking to somebody who tells you that his wife prefers Michael, her mother prefers Andrew, and his mother likes Alberto. If you ask him Which name do you prefer? you are asking him the name he prefers from among those three; if you ask him What name do you prefer? you are asking him the name he prefers, including any other name that isn't Michael, Andrew, or Alberto.

In your case, Which is correct? could be asked to a person who is talking about two or more options, for example You could do this or that. Your question is essentially asking Between this and that, what is correct?

  • I know this but i want To Understand is It More Usual To Use what Instead Of witch? Commented Jul 24, 2013 at 12:45
  • It all depends from what question you are asking. It's not a matter of preferring one instead of the other; so, which one is more usual to use is something that cannot be said.
    – apaderno
    Commented Jul 24, 2013 at 12:52
  • Can u explain more? Commented Jul 24, 2013 at 12:59
  • The words you are asking about have different meanings. (See my answer.) Asking which one is more common to use is like asking which is more common to use between dog and cat.
    – apaderno
    Commented Jul 24, 2013 at 13:05

What is used when you are asking a question that can have an unlimited number of possible answers.

What is your name? You can receive any answer!

Which is used when the options for the answer are limited.

Which one is the most beautiful? The red or the yellow? You can receive only two answers.

  • 1
    Bon, if you have only two options you should say "Which one is more beautiful", but if you have three or more than you can say "Which one is the most beautiful".
    – user114
    Commented Jul 23, 2013 at 20:06
  • 2
    @Carlo_R.: What you said there is very true, but you'll find that many native speakers will often say most in that circumstance (i.e., even when there are only two options, and more would technically be the more correct word).
    – J.R.
    Commented Jul 23, 2013 at 20:16

The difference is the number of possible options to choose from. So, if the number of possibilities is the whole universe, you ask "WHAT". If it is limited, you ask "WHICH".

Let me explain:

Q. What color shirt will you wear?

Here, the asker could accept any color as the answer. So, if you say, 'taupe', they might ask, "What is that?", but they won't say, "Wrong answer".

Q. Which color shirt will you wear?

Here the asker has laid down a limited number of colors to choose from. So, he could say:

...between red and gray...

Therefore, the answer "Blue" could be technically wrong. Again technically, the reply should be, "I don't like either. I'll wear blue."

Please note that what I said above is just an example to distinguish WHAT from WHICH. Therefore, simply answering "Blue" means, "I don't like either. I'll wear blue." That's why I used the word "technically".

So, to conclude,

  1. You use "WHAT" when you have to choose from an unlimited number of options
  2. You use "WHICH" to choose from an limited number of options.
  • A woman has twenty dresses to choose from: "What dress are you going to wear" and "Which dress are you going to wear" are both correct to my ears. But "What is the correct answer?" Suggests there is only one right solution to the question.
    – Mari-Lou A
    Commented Jan 2, 2021 at 9:38

'What' stands as the subject and 'which' is the object of the sentence, also 'which' can stands as subject of the which clause that replace the whole clause of the previous sentence. 'What' is used to ask an unknown thing while 'which' means a choice among several things.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .