Japanese Question Words: Who, What, When, Where, Why & How (2026)

Why Question Words Are the Key to Learning Japanese

Question words are the most powerful vocabulary investment in any language. With just eight core words — 何、誰、いつ、どこ、なぜ、どれ、どう、誰の — you can ask about literally anything. You do not need to know the answer to understand a topic; you just need to ask the right question and listen. This deck teaches the core words and then shows them in action in both polite and casual forms.

A key pattern: the どo-words family. どこ (where), どれ (which), どう (how), どんな (what kind) all start with ど. This is one of several predictable word families in Japanese that make the language easier to remember than it first appears.

The 8 Core Question Words

These single words work as complete questions on their own in casual speech. Memorize these first — everything else in the deck is built from them.

Polite Question Sentences

Add ですか？ to the core word and you have a polite, complete question suitable for strangers, shop staff, and any formal situation. These eight phrases cover the most common questions you will ask in daily life in Japan.

Casual Everyday Questions

These are the questions you ask friends — shorter, more direct, and ending in the casual の？ instead of ですか？. どうしたの？ (what happened?) and これなんて言うの？ (how do you say this?) are especially useful when living or traveling in Japan.

4 Tips for Using Japanese Question Words

1. The どo-word family

Japanese has a systematic set of question words all starting with ど: どこ (where), どれ (which), どう (how), どんな (what kind of), どちら (which direction / polite which). Learning one helps you remember the others — they all refer to an unknown from a set of options.

2. なに vs なん — the same word in different positions

何 is read as なに (nani) before most words, but なん (nan) before です, で, and consonant-starting words: これは何ですか (kore wa nan desu ka), 何個 (nanko), 何時 (nanji). The rule is phonetic — なん flows more naturally before certain sounds. Both are the same word; context tells you which reading to use.

3. の？ turns any statement into a casual question

Adding の？ (or just の with rising intonation) to almost any phrase makes it a casual question: 何してるの？ (what are you doing?), 日本人なの？ (are you Japanese?), どこ行くの？ (where are you going?). It is the casual equivalent of ですか？ and one of the most natural-sounding patterns in everyday Japanese.

4. なぜ vs なんで — formality matters

Both mean "why" but carry different registers. なぜ is neutral to formal — used in writing, polite speech, and serious questions. なんで is casual and emotive — the one you use with friends and in heated moments. Using なぜ with close friends sounds stiff; using なんで with a superior sounds blunt. Match the register to the relationship.

Frequently Asked Questions

How do I ask "how much?" in Japanese?

いくら (ikura) means "how much (money)?" — this is your essential shopping phrase: いくらですか？ (how much is it?). For "how many?" use いくつ (ikutsu) for general counts, or the specific counter + 何 (何人 for people, 何枚 for flat things, etc.). いくら and いくつ belong to the same question-word family but cover quantity rather than identity or location.

What is the polite way to ask "why"?

In polite or formal Japanese, use なぜですか？ or the longer それはなぜですか？ In very formal writing or speech, どうしてですか？ is also used. Avoid なんでですか？ in formal contexts — it sounds too casual and can come across as confrontational. どうして and なぜ are both safe in polite speech; なんで is for casual use only.

How do I ask "how do you say X in Japanese?"

The most natural phrase is 〜は日本語でなんて言うの？ (how do you say ~ in Japanese?) — casual. Polite version: 〜は日本語でなんと言いますか？. You can also hold up an object or point at something and say これなんて言うの？ (what do you call this?) — extremely useful for language learners exploring Japan in real life.

Can I use question words without a full sentence?

Yes — and this is one of the great things about Japanese. Just saying どこ？ with rising intonation is a complete, understood question ("where?"). 誰？ means "who?" いつ？ means "when?". Single-word questions work especially well in casual conversation when the context is clear. Japanese grammar allows for a level of abbreviation that would sound rude in English but is perfectly natural here.

Ask Anything in Japanese — Study These Words First

All 25 question word phrases above are available as a ready-made deck in Onigiri Anki. Questions are the fastest path to real conversation — study these with native Japanese audio and you will have the tools to keep any interaction going, no matter how limited your vocabulary is elsewhere.

Start on Web