JLPT N4・N5 Vocabulary – Difference between “たぶん” and “きっと”

Table of Contents

1. Difference between “たぶん” and “きっと”
2. たぶん
3. きっと
4. Let’s Compare
5. Summary
6. Quiz
7. Similar Articles
8. Comment

Q: Can “たぶん” and “きっと” be used interchangeably?

A: These two adverbs are mainly used with speculative words like “〜だろう” (probably) and “〜と思おもう” (I think).
However, because their degrees of certainty differ, they cannot be used interchangeably.

たぶん (JLPT N5)

[Meaning]
A state of predicting that something will happen or be the case, without being able to make a definite statement.

[Examples]
明日あしたはたぶん雨あめでしょう。
Tomorrow will probably be rainy.

A：明日あしたは何なにするの？
B：たぶん家いえにいるよ。
A: What are you doing tomorrow?
B: I’ll probably stay at home.

ゆみさんはたぶん来こないと思おもいます。
I think Yumi probably won’t come.

A：これで大丈夫だいじょうぶかな？
B：たぶん大丈夫だいじょうぶだと思おもうよ。
A: Do you think this is okay?
B: I think it’s probably okay.

きっと (JLPT N4)

[Meaning]
A state of predicting with certainty that something will happen.

[Examples]
明日あすはきっと雨あめです。
I’m sure it will rain tomorrow.

A：JLPTに受うかるか心配しんぱいだなあ。
B：たくさん勉強べんきょうもしたしきっと大丈夫だいじょうぶだよ！
A: I’m worried about passing the JLPT.
B: You’ve studied a lot, so it will be okay surely!

この店みせ、おいしいからきっと気きにいると思おもうよ。
This store has delicious food, so I’m sure you’ll like it.

彼かれはきっと成功せいこうしますよ。
He will surely succeed.

Let’s Compare

These two words express the degree of certainty, with “たぶん” indicating a lower degree and “きっと” indicating a higher degree of certainty.

“たぶん” is used when the speaker has less information to base their decision on and does not have strong confidence.

[Examples]
空そらがくもっているな。たぶん明日あしたは雨あめかな。
The sky is cloudy. It might rain tomorrow.
⇒ The fact that the sky is cloudy alone results in a low degree of certainty.

A：山田やまだくんはどこだろう。
B：かばんもないし、たぶん帰かえったと思おもうよ。
A: Where is Yamada-kun?
B: His bag is gone, so I think he probably went home.
⇒ B is not sure whether Mr. Yamada has gone home or not.

In contrast, “きっと” is used when the speaker has a certain amount of information that serves as a basis for their assumption, leading to a higher degree of certainty.

[Examples]
空そらがくもっているな。天気てんき予報よほうでは雨あめと言いっていたし、きっと明日あしたは雨あめだろう。
The sky is cloudy. The weather forecast said it would rain, so it will certainly rain tomorrow.
⇒ The information from the weather forecast increases the certainty.

A：山田やまだくんはどこだろう。
B：もう5時じ半はんだね。いつも5時じに帰かえるからきっと帰かえったよ。
A: Where is Yamada-kun?
B: It’s already 5:30. He always leaves at 5, I’m sure he went home.
⇒ Knowing that he always goes home at 5 o’clock increases the certainty.

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[きっと]

There are two uses of “きっと” that “たぶん” does not have.

The first one expresses the speaker’s intention or determination to certainly do something.

[Examples]
(わたしは) きっと成功せいこうしてみせる。 　
I will surely succeed.
　　　
きっと次つぎはもっといい結果けっかを出だします。 　
I will surely get better results next time.

The second one expresses a request or demand that the speaker wants the other person to fulfill.

[Examples]
きっとまた来きてくださいね。 　
Please surely come here again.
　　　
いつかきっと成功せいこうしてください。応援おうえんしています。
Please succeed someday. I’m cheering for you.

Summary

たぶん

• The speaker has little information to base their decision on and does not have strong confidence.

きっと

• The speaker has a certain amount of information that serves as a basis for their assumption, leading to somewhat strong confidence.
• It is also used when the speaker wants to express their determination to certainly do something or to make a strong request to the other person.

Quiz

Read the following sentence and choose the expression that fits the context from the options provided in the parentheses.

Click on the question to check the answer.

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