〜わけがない: 'There's No Way' / 'Impossible'
The denial it makes
〜わけがない declares that something cannot possibly be true. Literally わけ means "reason/logic," so わけがない reads as "there's no reason (for it to be so)" — logic leaves zero room for it. This is a confident conclusion, not a polite guess: the mood is はっきり言える ("I can say for sure") rather than たぶん ("probably"). You reach for it when you want to knock down a premise flatly, often with a touch of emphasis or emotion.
What it rests on
The judgement rests on the plain form of the predicate — you simply state the fact and let わけがない slam the door on it. Watch the join for な-adjectives and nouns:
| Word type | Attachment | Example |
|---|---|---|
| Verb (plain) | verb + わけがない | 来る → 来るわけがない |
| い-adjective | adj + わけがない | 安い → 安いわけがない |
| な-adjective | adj + な + わけがない | 暇 → 暇なわけがない |
| Noun | noun + である/な + わけがない | 嘘 → 嘘であるわけがない / 嘘なわけがない |
| Negative | plain neg + わけがない | 知らない → 知らないわけがない |
The same denial comes in three registers:
- わけがない — neutral, standard.
- わけはない — slightly more formal/written; は adds a touch of contrast ("certainly not that").
- わけない — casual speech, the が dropped: そんなの できるわけないじゃん。
How sure it sounds — and its neighbours
わけがない sits at the top of the certainty scale: total denial, no wiggle room. That strength is exactly what separates it from the look-alikes it gets confused with. First, the わけ family — this is the heart of N3 わけ confusion, since all three look alike but mean very different things:
| Pattern | Meaning | Nuance |
|---|---|---|
| 〜わけがない | "there's no way" / impossible | Total denial — logic rules it out |
| 〜わけではない | "it's not necessarily that…" | Partial denial — softens, not 100% |
| 〜わけにはいかない | "I can't (afford to) do it" | Can't for social/moral reasons |
Feel the drop in certainty from one to the next:
- 好きなわけがない = "There's no way I like it." (I definitely don't.)
- 好きなわけではない = "It's not that I particularly like it." (I might, a little.)
- 行かないわけにはいかない = "I can't not go." (Obligation, nothing to do with possibility.)
The closest cousin in strength is はずがない, and the two often overlap. The shade of difference is where the denial comes from:
- はずがない (see はず) — denial from expectation/reasoning: based on what should be, it can't be so. 彼が来ないはずがない ("he can't possibly not come — he said he would").
- わけがない — denial from logic/common sense: there's simply no reason it could be true. Often feels a touch more emphatic or emotional.
In everyday speech they're frequently interchangeable; when in doubt, both are natural for "there's no way."
In use
そんなに高いものが買えるわけがない。
そんなに たかい ものが かえる わけが ない。
There's no way I can afford something that expensive.
ヤッタンが宿題を忘れるわけがない。
ヤッタンが しゅくだいを わすれる わけが ない。
There's no way Yattan would forget his homework.
Strong confidence based on what you know about him.
毎日サボっていて、試験が簡単なわけがないよ。
まいにち サボっていて、しけんが かんたんな わけが ない よ。
Slacking off every day, there's no way the exam will be easy.
な-adjective takes な before わけがない.
先生がそんな失礼なことを言うわけがありません。
せんせいが そんな しつれいな ことを いう わけが ありません。
There's no way the teacher would say something that rude.
ありません = polite form of ない.
モチがこの本を読んでいないわけがない。いつも持ち歩いているもの。
モチが この ほんを よんでいない わけが ない。いつも もちあるいている もの。
There's no way Mochi hasn't read this book — he carries it around all the time.
Negative predicate (読んでいない) + わけがない = 'no way he hasn't.'
弟が一人でここまで来られるわけがないだろう。
おとうとが ひとりで ここまで こられる わけが ない だろう。
There's no way my little brother could get all the way here by himself.
Watch-outs
- Mixing up わけがない and わけではない. わけがない = total impossibility ("no way"); わけではない = partial ("not necessarily"). 高いわけがない ("no way it's expensive") ≠ 高いわけではない ("it's not that expensive").
- Forgetting な with な-adjectives and nouns. Say 静かなわけがない and 嘘である/なわけがない — never 静かわけがない.
- Treating it as a soft guess. わけがない is confident, not tentative. For "probably not," use 〜ないだろう or 〜ないと思う instead.
- Reaching for it when you mean obligation. "I can't skip it" is 〜わけにはいかない, not 〜わけがない.
The short version
- 〜わけがない = "there's no way" / "impossible" — confident logical denial.
- Attach to plain forms; な-adj + な, noun + である/な.
- Registers: わけがない (neutral), わけはない (formal), わけない (casual).
- わけがない (total) ≠ わけではない (partial) ≠ わけにはいかない (can't afford to).
- Close cousin: はずがない (denial from expectation).
Practice it
Choose わけがない, わけではない, or わけにはいかない to fit each sentence.
＿＿＿に入れるのに最もよいものを選びなさい。
そんなことが＿＿＿。
Frequently asked questions
What's the difference between わけがない and わけではない?
わけがない is a total denial — 'there's no way / it's impossible': できるわけがない ('no way I can do it'). わけではない is a partial denial — 'it's not necessarily that…': できないわけではない ('it's not that I can't do it'). One rules it out completely; the other just softens.
Is わけない rude or wrong?
It's just casual. Dropping the が (わけない) is normal in everyday speech: そんなの分かるわけないよ. In writing or formal speech, use わけがない or わけはない.
How does わけがない differ from はずがない?
Both deny strongly. はずがない denies based on expectation ('it shouldn't be, so it can't be'); わけがない denies based on logic/common sense ('there's no reason it could be'). In casual conversation they often overlap.
How do I attach わけがない to a noun or な-adjective?
Use な or である as the link: 嘘なわけがない / 嘘であるわけがない ('there's no way it's a lie'), 暇なわけがない ('no way I'm free'). Plain verbs and い-adjectives attach directly: 来るわけがない, 安いわけがない.
Where 〜わけがない fits
Shaky on this? Get these solid first
- 〜わけだ · N3 — 〜わけだ marks a logical conclusion that naturally follows from facts: 'so that means,' 'no wonder,' 'it follows that.' Learn the formation and how it differs from はず and から.
Don't confuse it with
- 〜わけではない · N3 — 〜わけではない softly corrects an assumption: 'it's not that…' / 'it doesn't necessarily mean…'. Learn the formation, the casual わけじゃない, and how it differs from わけがない.
- 〜わけにはいかない · N3 — 〜わけにはいかない means you can't do something for social, moral, or psychological reasons. Learn the form, the double-negative 〜ないわけにはいかない ('have to'), and how it differs from ことができない.
- 〜はず · N4 — はず expresses a logical expectation based on reason: 来るはずだ ('should come'). Learn how it attaches to plain forms, plus はずがない ('can't possibly') and はずだった ('was supposed to').
More N3 grammar to explore
Keep going with related patterns at the same level:
- 〜にとって — 〜にとって marks whose viewpoint an evaluation is made from: 私にとって大切 ('important to me'). Learn the formation, にとっての + noun, and how it differs from として.
- 〜について — 〜について marks the topic you talk, think, or write about: 日本の文化について話す. Learn the form, the についての + noun pattern, についても, and how it differs from に関して.
- 〜という — 〜という names things (「ヤッタン」という犬), wraps hearsay (来ないという), and packages a clause into a noun (失敗したという事実). Learn all three N3 uses.
- 〜として — 〜として marks a role or capacity: 先生として ('as a teacher'). Learn the formation, the variants としては and としても, the set phrase 〜は別として, and how it differs from にとって.
- 〜とすれば / 〜としたら / 〜とすると — 〜とすれば, 〜としたら, and 〜とすると mean 'supposing that' or 'if we assume': set up a hypothesis, then reason from it. Learn the nuances, formation, and how they differ from なら.