GrammarJLPT N5
→ should be
Be Supposed / Expected To
JLPT N5Fixed phraseNeutral
はずだ expresses the speaker's confident expectation or logical conclusion that something should be the case, based on reasoning, evidence, or prior knowledge. It conveys the idea that something is supposed to happen, ought to be true, or is expected to be so according to what the speaker knows. Unlike だろう, which expresses a softer guess or probability, はずだ carries a stronger sense of certainty grounded in logic or information — the speaker has a reason to believe the statement is true. It differs from つもりだ, which expresses the subject's own intention, whereas はずだ is about the speaker's expectation regarding a situation or another person. It also contrasts with べきだ, which expresses moral obligation rather than logical expectation. The negative counterpart はずがない means "there is no way that…" and expresses strong disbelief. はずだ is used across casual and formal registers, with the formal form being はずです.
Functions
#1 Logical expectation based on evidence or knowledge
Structure
Verb (plain form) + はずだ
田中さんはもう家に着いたはずです。
Here はずだ expresses the speaker's confident expectation that Tanaka has already arrived home, based on some reasoning — perhaps knowing what time he left or how long the trip takes. The speaker is not guessing randomly but drawing a logical conclusion from available information. The past tense verb 着いた precedes はずだ because the expected event (arriving) is believed to have already occurred.Tanaka should have arrived home by now.
Structures
- Verb (plain form)
- Verb (plain form) + はずだ
- い-Adjective
- い-Adjective + はずだ
- な-Adjective
- な-Adjective + な + はずだ
- Noun
- Noun + の + はずだ
Common mistakes
A common mistake is confusing はずだ with つもりだ. While つもりだ expresses the speaker's or subject's own intention ("I intend to…"), はずだ expresses an expectation about a situation based on logic or evidence. Another frequent error is using はずだ for pure guesses without any basis — if you have no reason to believe something, だろう or かもしれない would be more appropriate. Learners also sometimes write な-adjective + はずだ without the connecting な (e.g., saying 静かはずだ instead of the correct 静かなはずだ), or noun + はずだ without の (e.g., 休みはずだ instead of 休みのはずだ). Finally, confusing the negative forms is common: Verb（ない）+ はずだ means "it is expected that something is not…," while はずがない means "there is no way that…" and carries much stronger denial.
Related
べきだつもりだにちがいないだろうはずがない