きっと means “surely,” “I’m sure,” or “must.” It is an adverb that tells the listener how confident you are about something you cannot check yet: 田中さんはきっと来ますよ — “Tanaka will come, I’m sure.”
The important word there is yet. きっと is about expectation — the future, other people’s feelings, the cause of something you can only guess at. It is not for facts you already know, and it is not for rules. That second limit is where most learners go wrong, because English “surely” and “definitely” cover more ground.
きっと = “I’m convinced this is (or will be) true.” It is strong personal confidence, not a guarantee.
What does きっと mean?
きっと marks a strong guess, somewhere around 80–90% sure. It often softens into warm encouragement, because telling someone “you’ll surely pass” is both a prediction and a kind word.
- 明日はきっと晴れるでしょう。 — It’s bound to be sunny tomorrow.
- 電気が消えている。きっと留守だ。 — The lights are off. They must be out.
- あなたならきっとできるよ。 — If it’s you, I’m sure you can do it.
It can also express a firm promise about your own future action: きっと返します — “I’ll pay you back, I promise.” This use is a little old-fashioned; in everyday speech people more often say 必ず or 絶対.
How to form きっと
きっと is an adverb, so there is nothing to conjugate. Put it near the start of the sentence or right before the part you are confident about. The sentence ending is where the real work happens: きっと pairs with endings that express a guess or a conviction.
| Ending | Example | Feel |
|---|---|---|
| でしょう／だろう | きっと雨が降るでしょう | forecast, polite guess |
| と思う | きっと大丈夫だと思う | personal conviction |
| はずだ | きっと届いているはずだ | expectation based on facts |
| んだ／のだ | きっと疲れているんだ | explaining a situation |
| ます／plain | きっと来ます | confident statement |
Using a guess ending together with きっと is not repetitive in Japanese. It is the normal way to sound confident without claiming certainty. A bare statement like きっと来ます is also fine; it sounds a little more assertive.
When is きっと used?
- Predictions: weather, results, what someone will do. きっと喜ぶよ — “She’ll love it, I’m sure.”
- Explaining something you can only infer: 返事がない。きっと忙しいんだ — “No reply. They must be busy.”
- Encouragement: 大丈夫、きっとうまくいくよ — “Don’t worry, it’ll work out.” This is one of its most common uses in conversation.
- Hopes phrased as expectations: いつかきっと会えるね — “We’ll meet again someday, I’m sure.” Song lyrics and letters use this a lot.
きっと is neutral in register. It works in plain speech with friends and in polite speech with です／ます.
きっと example sentences
田中さんはきっと来ますよ。
Tanaka will come, I’m sure of it.
明日はきっと晴れるでしょう。
It’s bound to be sunny tomorrow.
電気が消えている。きっと留守だろう。
The lights are off. They must be out.
あなたならきっと合格できるよ。
You of all people will pass, I know it.
毎日練習すれば、きっと上手になります。
If you practise every day, you’re sure to get better.
元気がないね。きっと疲れているんだと思う。
He seems down. I bet he’s just tired.
Notice that every sentence is about something the speaker has not confirmed: tomorrow’s weather, a future exam, why a friend looks tired. That is the territory where きっと lives.
Nuance of きっと
きっと is subjective. It reports how sure you feel, not what the evidence proves. If you want to say something follows logically from facts (“the parcel was sent Monday, so it should have arrived”), はずだ carries that logic; きっと only adds your confidence on top.
Because it is a feeling, きっと works poorly in three places:
- Known facts. You don’t say きっと今日は月曜日です if you’re looking at the calendar.
- Requests and commands. “Please be sure to come” is not a guess, so きっと can’t go there.
- Habits and rules. “I always drink coffee in the morning” is a routine, not a prediction.
For the last two, Japanese uses 必ず (かならず): 必ず来てください, 毎朝必ずコーヒーを飲む.
Mind the ending. きっと and かもしれない clash: one says “I’m sure,” the other says “maybe.” Pair きっと with でしょう, だろう, と思う, or a plain statement.
きっと vs たぶん
Both are guessing adverbs, and both take でしょう or だろう at the end. The difference is how sure you are.
On a rough scale: もしかしたら〜かもしれない (maybe) → たぶん (probably) → きっと (surely) → 必ず／絶対 (certainly, no doubt). When a friend is nervous before an exam, きっと大丈夫 comforts them; たぶん大丈夫 does not.
Common mistakes with きっと
A request is not a prediction. “Be sure to…” with てください needs 必ず.
きっと (sure) and かもしれない (maybe) contradict each other. Choose one level of certainty.
For a fixed habit (“without fail every morning”), use 必ず. きっと is for things you are predicting, not things you routinely do.
Is きっと on the JLPT?
Yes. きっと is on the N4 vocabulary and grammar lists. Questions usually test it as an adverb choice: which of きっと, 必ず, たぶん, or ぜひ fits the sentence ending.
At N4 you should be able to:
- Pair きっと with でしょう, だろう, と思う, or はずだ
- Choose 必ず, not きっと, before てください and for habits
- Rank きっと, たぶん, and かもしれない by certainty
A classic item: 明日のパーティーには（ ）来てくださいね。 The ending てください rules out きっと and たぶん; the answers that fit are 必ず or ぜひ, depending on whether the speaker is insisting or warmly inviting.
Practice questions for きっと
Show answer
大丈夫、きっとうまくいくよ。 — Don’t worry, I’m sure it’ll go well.
Show answer
寝る前に必ず歯をみがきます。 — I always brush my teeth before bed. (A habit, so 必ず.)
Show answer
電話に出ない。きっと寝ているんだろう。 — They’re not picking up. They must be asleep.
Show answer
彼はきっと来るだろう。 — I’m sure he’ll come. (Or: 彼は来るかもしれない。 — He might come.)
Learning path for きっと
Related grammar to review next
- かもしれない — the “maybe” end of the scale; never combine it with きっと.
- はずだ — expectation based on facts or logic, often paired with きっと.
- でしょう — the polite guess ending that きっと most often sits with.
- ぜひ — the adverb for requests and wishes, where きっと doesn’t fit.
Learn きっと with Hane
Hane tests きっと against 必ず, たぶん, and ぜひ in real sentences, so you learn which adverb each ending allows. Practise N4 adverbs in Hane.
FAQ about きっと
What does きっと (kitto) mean in Japanese?
きっと (kitto) means “surely; certainly”. It is JLPT N4 grammar. きっと marks a strong guess, somewhere around 80–90% sure. It often softens into warm encouragement, because telling someone “you’ll surely pass” is both a prediction and a kind word.
How do you form きっと (kitto)?
きっと is an adverb, so there is nothing to conjugate. Put it near the start of the sentence or right before the part you are confident about. The sentence ending is where the real work happens: きっと pairs with endings that express a guess or a conviction.
What is the difference between きっと and たぶん?
きっと: strong confidence. たぶん: ordinary probability.
What is an example sentence with きっと (kitto)?
田中さんはきっと来ますよ。 — Tanaka will come, I’m sure of it.