どうして means why or how come. It is the everyday question word you use when you want someone to explain the reason behind something: why they did it, why it happened, or why things are the way they are.
どうして asks for an explanation, so the answer usually ends in から: 「どうしてですか。」「雨だからです。」
What does どうして mean?
どうして is a question word, like なに (what) or どこ (where). It sits near the start of the question and asks for a reason. The natural English is almost always “why” or “how come”:
- どうして来なかったんですか。 — Why didn’t you come?
- どうしてですか。 — Why is that? / How come?
The second line shows something English speakers find handy: どうしてですか works on its own as a reaction. When someone tells you “I’m quitting my job” or “The shop is closed today,” you can simply answer どうしてですか and they will explain.
Because どうして asks for a reason, the reply normally gives one with から (because): 病気だったからです (Because I was sick). Learning the question and the answer as a pair is the fastest way to use どうして in real conversation.
How to form どうして
どうして does not conjugate and does not attach to anything. You place it at the front of a normal question. What matters is the ending of that question.
There are three common endings:
- 〜んですか (polite): どうして行かないんですか。 — Why aren’t you going?
- 〜の？ (casual, rising tone): どうして行かないの？ — Why aren’t you going?
- 〜ますか / 〜ですか (plain polite): どうして日本が好きですか。 — Why do you like Japan?
The んですか ending is the one to aim for. It turns the question into “What’s the story behind this?”, which fits a why-question perfectly. Before んですか and の, use the plain form: 行く → 行くんですか, 来なかった → 来なかったんですか. Nouns and な-adjectives take な: 好き → 好きなんですか, 雨 → 雨なんですか.
When is どうして used?
You reach for どうして in three kinds of situations:
- Asking about something you noticed. Your friend is wearing a coat in summer, or a classmate looks tired. どうしてコートを着ているの？
- Following up on news. Someone says they are moving to Osaka. You answer どうしてですか to invite the reason.
- Complaining or showing surprise. どうして！ on its own, or どうして言わなかったの？ (Why didn’t you tell me?), expresses frustration.
Register: どうして is fine in both casual and polite speech. It is the most common “why” in conversation. In essays, news, and formal explanations, writers often switch to なぜ, and in very casual talk among friends you will hear なんで.
どうして example sentences
Look at where どうして sits in each sentence: at or near the front, before the part being questioned. In the last example the tone depends on your voice. Said softly, it is a worried question. Said sharply, it is an accusation.
Nuance of どうして
どうして asks the listener to explain themselves. That is why it pairs so naturally with んですか, the ending for asking about background and circumstances.
This also means どうして can put pressure on the listener. A parent saying どうして宿題をしなかったの？ is not curious; they want an excuse. When you ask about a choice someone made, a gentle tone and the んですか ending keep the question friendly. どうしてですか said to a teacher or boss after they give an instruction can sound like you are challenging them, so in that situation many speakers ask about the reason more indirectly or simply accept the instruction.
どうして vs なぜ
Both words mean “why,” and in most sentences you can swap them without changing the meaning. The difference is register.
A quick way to remember the three “whys”: なんで is for friends, どうして is for almost everyone, and なぜ is for writing and formal speech. If you only learn one at N5, learn どうして. A different word that learners mix up with どうして is どうやって, which asks “how” in the sense of method. See the mistakes below.
Common mistakes with どうして
English "how" can mean method or reason. どうして only asks the reason ("Why are you going to the station?"). For directions or method, use どうやって.
The answer to a why-question needs から (or ので). Without it, you have just stated a fact, not given it as the reason.
な-adjectives and nouns need な before んですか. い-adjectives and verbs attach directly: 高いんですか, 行くんですか.
Is どうして on the JLPT?
Yes. どうして is core JLPT N5 vocabulary and grammar. It is especially common in the listening section, where many questions follow the model 「男の人はどうして〜ましたか。」
- Pick どうして (not どうやって or どこ) when the answer choices are reasons
- In listening, wait for the から clause: that is where the answer is
- Recognize なぜ as a formal synonym in reading passages
In listening, speakers often give a wrong reason first and then correct it ("It's not because of X, it's because of Y"), so keep listening until the end.
Practice questions for どうして
Show answer
どうして日本語を勉強しているんですか。 — Why are you studying Japanese?
Show answer
どうしてパーティーに来なかったの？ — Why didn't you come to the party?
Show answer
バスが遅れたからです。 — Because the bus was late.
Show answer
どうして京都が好きなんですか。 — Why do you like Kyoto?
Learning path for どうして
Related grammar to review next
- から — the standard way to answer a どうして question: 〜からです.
- ので — a softer reason word, useful when your answer should sound polite and less blunt.
- んです — the ending that どうして questions most often use: どうして〜んですか.
- どうやって — asks “how” (by what method), the question word most often confused with どうして.
- か — the question particle behind どうして〜ですか.
Learn どうして with Hane
Hane drills どうして together with its から answers, so asking and explaining reasons becomes automatic. Start practicing with Hane.
FAQ about どうして
What does どうして (doushite) mean in Japanese?
どうして (doushite) means “why or how come”. It is JLPT N5 grammar. どうして is a question word, like なに (what) or どこ (where). It sits near the start of the question and asks for a reason.
How do you form どうして (doushite)?
どうして does not conjugate and does not attach to anything. You place it at the front of a normal question. What matters is the ending of that question. どうして + plain-form clause + んですか There are three common endings: - 〜んですか (polite): どうして行かないんですか。
What is the difference between どうして and なぜ?
どうして: spoken, everyday. なぜ: written, formal.
What is an example sentence with どうして (doushite)?
どうして日本語を勉強しているんですか。 — Why are you studying Japanese?