だろう means probably or right?. It is a JLPT N5 Japanese grammar pattern used to make a guess or seek agreement in casual or written style.
This grammar point appears often in beginner conversations, textbooks, and JLPT-style reading questions. If you want to express probability without sounding completely certain, だろう is a useful pattern to learn early because it connects directly to everyday communication.
What does だろう mean?
Use だろう when you want to show that the speaker thinks something is likely but not fully confirmed.
Natural translations include:
- probably
- I suppose
- right?
The exact English translation changes with context. The important point is to understand what job the pattern is doing in the sentence, not to memorize only one English phrase.
How to form だろう
Plain form + だろう; noun / な-adjective often use だろう directly
Examples of the pattern:
- 雨が降るだろう
- 学生だろう
- 静かだろう
Pay attention to the form that comes before the grammar point. Many beginner mistakes happen because the learner understands the meaning but attaches the pattern to the wrong word form.
When is だろう used?
Use だろう in situations like:
- making predictions
- thinking aloud
- asking for agreement in casual speech
Tone and register:
- casual, masculine in some conversation, and common in written predictions
- Common in daily speech, textbook examples, and beginner JLPT questions
だろう example sentences
- 明日は雨が降るだろう。 — It will probably rain tomorrow.
- 彼はもう家にいるだろう。 — He is probably already home.
- これは高いだろう。 — This is probably expensive.
- 君も行くだろう？ — You are going too, right?
- 試験は難しいだろうと思う。 — I think the exam will probably be difficult.
Read the Japanese sentence first, then check whether the English translation matches the feeling of the whole sentence. This helps you avoid translating each piece too literally.
Nuance of だろう
The key nuance is a judgment based on expectation rather than direct proof.
This matters because learners often know the dictionary meaning but miss the speaker’s intention. In real Japanese, grammar points show attitude, politeness, contrast, certainty, desire, or context. For だろう, focus on how the pattern changes the role of the sentence.
For example:
- In conversation, it can sound confident but not absolute.
- Compared with でしょう, it feels less polite and often more casual.
だろう vs でしょう
Both だろう and でしょう can be related in beginner Japanese, but they are different.
だろう:
- plain counterpart of でしょう
- can sound rough or masculine in direct conversation
でしょう:
- polite and safer with strangers
- also used in weather forecasts and polite predictions
Quick contrast examples:
- 彼は来るだろう。— He will probably come.
- 彼は来るでしょう。— He will probably come.
If you are unsure which one to use, ask what the sentence is trying to do: define something, ask something, show a reason, mark a subject, describe a desire, or connect ideas.
Common mistakes with だろう
Watch out for these mistakes:
- Using だろう in polite conversation when でしょう is safer
- Treating it as a confirmed fact
- Adding it after polite ます forms
A good study habit is to make one simple original sentence, then change only one part of it. That makes the function of the grammar point easier to see.
Is だろう on the JLPT?
Yes. だろう is commonly taught as JLPT N5 grammar.
That means learners should be able to:
- recognize it in reading
- understand its nuance in context
- use it in simple original sentences
For test preparation, do not only memorize the English gloss. Practice identifying the word before and after the grammar point, because JLPT questions often test structure and context together.
Practice questions for だろう
Try making your own sentences with these prompts:
- Predict tomorrow’s weather.
- Guess where your friend is.
- Ask “You understand, right?” casually.
Keep the sentences short at first. Once the form feels natural, add time words, places, reasons, or contrast to make the sentence more realistic.
Learn だろう with Kanjiru
If you want to review だろう together with kanji, vocabulary, and other JLPT N5 patterns, Kanjiru helps you practice Japanese in short, focused sessions.
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