か (question)

• Reading: か
• Romaji: ka
• Formation: Statement + か

Meaning

A sentence-final particle that marks the preceding sentence as a question. Adding か to the end of a statement transforms it into a yes-no question or, with an interrogative word, a content question.

か at the end of a sentence is the most standard way to form questions in Japanese. In polite speech (です/ます forms), か is virtually always used. In casual speech, か can sound blunt or even aggressive, so rising intonation alone often replaces it. With interrogative words like 何, どこ, いつ, だれ, か confirms the sentence as a question. Note that in polite yes-no questions, the intonation typically rises, while in polite information questions it may stay flat. Learners sometimes add か after casual forms when speaking to friends, which can sound confrontational — this is a common sociolinguistic pitfall.

Examples

1. これは何ですか。 What is this?
2. 明日は暇ですか。 Are you free tomorrow?
3. 駅はどこですか。 Where is the station?

Usage Guide

Context: spoken, written, everyday

Tone: inquisitive

Do Say

• この電車は新宿に止まりますか。
• 週末は何をしますか。
• お名前は何とおっしゃいますか。
• 今日の会議は何時からですか。

Don't Say

• これは何です。(Omitting か in polite speech makes it sound like an incomplete statement) → これは何ですか。
• お前はどこに行くか。(Using か with very casual pronouns sounds aggressive or interrogatory) → どこに行くの。
• あなたは学生だか。(Placing か directly after だ in casual form — use ですか or drop か entirely) → あなたは学生ですか。

Origin & History

The interrogative か traces back to Old Japanese, where it served as a bound particle expressing doubt or questioning. Its function has remained remarkably stable across centuries of language change.

Cultural Context

Generation: All ages

Social background: Universal