Can You Correctly Use “kitto” and “zettaini” and “kanarazu”?

Japanese has three adverbs that all mean something like “surely” or “definitely” in English — きっと, 絶対ぜったいに, and 必かならず — but they carry very different levels of confidence and are used in different situations. This article will help you choose the right one every time.

Yuka

きっと、絶対に、必ず ってどう違うの？ (How are kitto, zettai ni, and kanarazu different from each other?)

Rei

確信の強さが違うよ。きっと は約60%、絶対に は約85%、必ず は約95%くらいの確信度だよ。 (They differ in strength of certainty. Kitto is about 60%, zettai ni about 85%, and kanarazu about 95%.)

At a Glance

きっと (kitto) — “I’m sure ___” (~60%)

“きっと” is used when you are making a guess you are fairly confident about — roughly 60-70% sure. It can also express hope even when something is unlikely. Notably, きっと has a positive, encouraging tone.

Sample

Yuka

森田もりたくんの言いったことはきっと嘘うそだと思おもうよ！ (I’m sure what Morita said was a lie!) (morita kun no itta koto wa kitto uso da to omou yo!)

Rei

きっと試験しけんに受うかるよ！ (I’m sure you’ll pass the exam!) (kitto shiken ni ukaru yo!)

絶対に (zettai ni) — “Definitely ___” (~85%)

“絶対ぜったいに” expresses much stronger confidence — around 80-90%. It can also be used as a command or a strong prohibition (e.g., 絶対にぜったいにするな! — “Absolutely do not do that!”).

Sample

Yuka

絶対ぜったいに治なおるよ！ (You’ll definitely recover!) (zettai ni naoru yo!)

Rei

今日きょうの晩御飯ばんごはんは絶対ぜったいカレーだな！ (I’m positive today’s dinner is curry!) (kyō no bangohan wa zettai karē da na!)

必ず (kanarazu) — “Without a Doubt ___” (~95%)

“必かならず” carries the highest certainty — around 90-100%. It is used when something is considered nearly inevitable or when making a strong commitment. It often appears in formal writing and serious promises.

Sample

Yuka

必かならず息子むすこさんに会あえると思おもいますよ！ (I have no doubt you will see your son.) (kanarazu musuko san ni aeru to omoimasu yo!)

Rei

こんな小ちいさいことなんて必かならず乗のり越こえれるよ！ (You’ll no doubt get over something this small!) (kon’na chīsai koto nante kanarazu norikoereru yo!)

Quick Quiz

Choose the most appropriate word: きっと / 絶対に / 必ず.

Q1. _____ また会おう！約束だよ。(Let’s _____ meet again! It’s a promise.) → Answer: 必ず (strongest commitment, a promise)

Q2. 彼女は _____ 喜ぶと思うよ。(I’m sure she’ll be happy.) → Answer: きっと (a guess with hope, ~60%)

Q3. この映画は _____ おもしろいよ！(This movie is _____ interesting!) → Answer: 絶対に (strong assertion, ~85%)

Remember the confidence ladder: きっと (hopeful guess, ~60%) → 絶対ぜったいに (strong assertion, ~85%) → 必かならず (near certainty or commitment, ~95%). When in doubt, listen for the emotion behind the sentence — encouragement and hope lean towards きっと, strong claims lean towards 絶対に, and solemn promises or near-certainties call for 必ず.

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