かどうか (ka dou ka) Meaning Japanese Grammar - Whether or Not

Author Anna Baffa Volpe for article 'かどうか (ka dou ka) Meaning Japanese Grammar - Whether or Not'

Anna Baffa Volpe

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かどうか (ka dou ka) Meaning Japanese Grammar - Whether or Not

The expression かどうか (ka dou ka) is used when we express doubt and uncertainty about whether an action is performed or not or whether it was performed in the past or not.

I don't know whether or not, if or not.

In this post we learn more about the meaning of かどうか, how it is formed and when かどうか is used through real example sentences.

かどうか Whether or not

かどうか is a widely used expression in Japanese, in situations of doubt, ambiguity and lack of clarity.

We do not know whether an action will be performed or not or we are not sure about a certain condition and situation.

We need to ask and verify to be sure.

Sentence A + かどうか + Sentence B

かどうか combines 2 sentences:

  • in the first one the it is expressed the fact, the action
  • in the second one, we often find in colloquial context the verb ()からない don't know if from the dictionary form ()かる understand, know.

The second sentence uses verbs and expressions of various kinds.

We can find the following verbs after かどうか:

  • ()know
  • ()かる know, understand
  • (たし)かめる check, make sure
  • (たず)ねる ask, enquire
  • (まよ)be in doubt, hesitate


He asked his wife whether or not she would come with him.


I'm not sure whether or not I should talk to her about it.

How かどうか is formed

The expression is formed

  • by the interrogative particle か which replaces in Japanese the question mark ?
  • the interrogative pronoun どう meaning how?


Do you know if it will be sunny tomorrow?

()れるか()れないか: Is it sunny or isn't it sunny?

Verb in the plain form+かどうか+Verb or Phrase


I don't know whether or not I can go back to Japan this year.

かどうか is often preceded by a verb in the potential form


I don't know whether or not I can go.

Noun+かどうか+Verb or Phrase

Or we can also use:

Noun+である+かどうか+Verb or Phrase

Example using the noun ()()feeling, sensation


I want to ask him whether or not he feels the same.

Noun (しん)(じつ) truth, reality


I don't know whether or not that is true.

い Adjective+かどうか+Verb or Phrase

い Adjective: 美味(おい)しい good-tasting, delicious


I don't know whether or not this dish is delicious.

な Adjective without な+かどうか+Verb or Phrase

な Adkective: ()きな favourite, preferred


I don't know whether or not my friend likes Japanese food.

(げん)()な: energetic, vigorous


Did you ask her how she was?

⇨ Did you ask her if she's okay or not?

Examples of かどうか


Ask him if he will attend the meeting.


I doubt whether or not John will come on time.

  • (うたが)わしい is a い Adjective and means doubtful and the verb from which it is derived (うたが)doubt


I have to decide whether or not to depart.