short form + はずです: Beginner’s Guide to Saying “I’m sure / It should be …” in Japanese

Introduction

Want to say “It should be sunny tomorrow” or “I’m sure he’s a student”? Use short form + はずです.

This pattern states a strong expectation or logical belief based on what you know (evidence, common sense, schedule, etc.). It’s stronger than “maybe,” but not 100% certain like a fact.

1. Meaning & When to Use

short (plain) form + はずです = “I’m sure that… / It should be …”

Use it when you have good reasons (information, logic, past statements) to expect something is true or will happen.

明日あしたは晴はれるはずです。
It should be sunny tomorrow.

あのドレスは高たかいはずです。
That dress should be expensive.

Think: “Given X, it really should be Y.” Not a guess out of nowhere.

2. How to Form It (attach はずです to the short form)

Use the plain/short form (not ます-form) right before はずです.

Verbs

adjectives and nouns

i-adjective: 高い (takai = tall / high / expensive)

na-adjective: 静かな (shizuka na = quiet)

Noun: 学生 (gakusei = student)

If you’d like to review short [plain] form, please see these articles.

• How to Use Japanese Short Forms (Plain Forms) for Casual Conversations
• How to Use Japanese Plain Form (Short Form) for Adjectives and Nouns
• How to Use Japanese Past Tense Plain Form (Short Form) – Verbs in Casual Conversation
• How to Use Japanese Plain Form Past Tense (Short Form) for Adjectives and Nouns

Past form: ～はずでした

You can also say 〜はずでした to mean “was supposed to…” / “should have…”.

Example: 会議かいぎは三時さんじに始はじまるはずでした。= The meeting was supposed to start at three.

What is はず?

はず is a noun meaning something like “expectation” or “what is naturally expected.”
That is why nouns use の before it, and na-adjectives use な before it.

Also, はず is not usually used by itself. It normally follows a verb, adjective, noun, or a demonstrative expression such as その.

はず can also modify a noun: ～はずの + noun

You can also use ～はずの + noun when you want to modify a noun.

It means “the [noun] that was supposed to…” or “the [noun] that should be…”.

Example: 玄関げんかんの前まえに置おいたはずの傘かさがなくなっていた。= The umbrella that I was sure I had left in front of the entrance was gone.

3. Example Sentences

あっちに東京駅とうきょうえきがあるはずです。
Tokyo Station should be over there.

会議かいぎは三時さんじに始はじまるはずです。
The meeting should start at three.

その店みせは、日曜日にちようびは休やすみのはずです。
That shop should be closed on Sundays.

明日あしたは雨あめが降ふらないはずです。
It shouldn’t rain tomorrow.

4. Usage Notes

• Evidence-based: Use はずです when you have a reason (schedule, rule, what someone said, obvious logic).
• Stronger than だろう／と思う: はずです = confident expectation; だろう/でしょう = “probably.”
• Politeness: はずです is neutral-polite. Plain form はずだ is casual.
• Nouns take の: 学生のはずです (not 学生はずです).
• Same subject not required: You can talk about anyone/anything, as long as your reason makes sense.
• Not for the speaker’s own intention: はずです is generally not used for the speaker’s own intentional future actions, because the speaker already knows their own intention. In that case, use 〜つもりです or 〜ようと思っています instead.
  • ✅ 明日あしたの朝あさは早はやいので、マイクさんは今夜早こんやはやく寝ねるはずです = Mike should go to bed early tonight.
  • ✖ 明日あしたの朝あさは早はやいので、私わたしは今夜早こんやはやく寝ねるはずです (I have to get up early tomorrow morning, so I plan to go to bed early tonight.)
    • ✅ 明日あしたの朝あさは早はやいので、私わたしは今夜早こんやはやく寝ねるつもりです
    • ✅ 明日あしたの朝あさは早はやいので、私わたしは今夜早こんやはやく寝ねようと思おもっています

Evidence-based: Use はずです when your expectation is backed by concrete reasons, such as:

• Schedules or plans: 会議かいぎは3時じに始はじまるはずです。 (The meeting should start at 3. → based on the schedule)
• Rules or common knowledge: その店みせは日曜日にちようびが休やすみのはずです。 (That shop should be closed on Sundays. → based on their usual hours)
• Information you heard/were told: 彼かれはもうすぐ来くるはずです。 (He should be here soon. → based on what he said)
• Logical deduction: あのドレスは高たかいはずです。 (That dress should be expensive. → based on its appearance/brand)

It’s not just a random guess; there’s a logical foundation for your belief.

5. Practice Time!

Convert each cue into a sentence with はずです.

6. Common Mistakes (and quick fixes)

7. Related Grammar

• ～にちがいない = “must be / no doubt” (even stronger certainty, written-ish).
• だろう／でしょう = “probably” (softer).
• はずがない／ないはずだ = “can’t be / there’s no way.”
  • This is the strong negative form of ~hazu desu, expressing that something cannot possibly be true or happen, based on strong evidence or logic.
  • Example: そんなことはあるはずがない。 (There’s no way such a thing could happen.)

Pro Tip: Expressing Unexpected Outcomes with ~hazu nanoni

Sometimes, what should be true isn’t. When you have a strong expectation based on evidence, but the reality is different, you can use ~hazu nanoni (〜はずなのに) to express surprise or disappointment. This means “It should be/have been…, but [it’s not/it didn’t happen].”

• 彼かれが来くるはずなのに、まだ来きていません。(He should be here by now, but he isn’t here yet.)
• 簡単かんたんなはずなのに、この問題もんだいが解とけません。(It should be easy, but I can’t solve this problem.)

8. FAQ

Conclusion

You can now:

• ✅ Attach はずです to the short form of verbs/い-adjs, な + はず for な-adjs, and N + の + はず for nouns.
• ✅ Use it to express a confident, evidence-based expectation: “I’m sure… / It should be…”.
• ✅ Avoid common slip-ups (ます-form, missing の after nouns, mixing polite forms before はず).

Practice by writing three things you’re sure about this week (based on schedules, rules, or what you heard) using はずです—it’ll click fast.