As I understand, they are both very close in terms of meaning.



Both sentences would mean: "It's not that I cannot sing, it's just that I get embarrassed in front of others."

I'm pretty sure there is a slight difference in nuance, that I can't quite grasp yet.

Is it a matter of opposing the belief of someone that you can't? (while the other is plainly a statement?)

  • する doesn't work like "(when I) do" in this context. See: Can する substitute a previously used verb?
    – naruto
    Sep 26, 2022 at 4:07
  • I'm a bit confused, was this comment meant for another post?
    – 悪戯猫
    Sep 26, 2022 at 10:52
  • I wanted to point out "人前ですると" made little sense here. You wrote すると because you thought it's a correct way of saying "if I do", right?
    – naruto
    Sep 27, 2022 at 2:57
  • Oh, I just saw the original... It was a random copy-paste example, now that you mention it it makes little sence indeed. I didn't even bother to read it to be honest, I focused mainly on the difference between the 2 points. Thanks for pointing it out!
    – 悪戯猫
    Sep 27, 2022 at 18:19

2 Answers 2


There is very little difference, and they are interchangeable most of the time. Still, I feel the speaker is more aware of the previous context when わけではない is used. That is, a sentence using わけではない tends to have a nuance of "that is not to say", "that doesn't mean" or "I'm not saying". ことはない is a relatively "plain" double-negative sentence.


Not sure if this is what you are looking for, but -タ form seems to behave differently for the two constructions. As I see it, なかったことはない coincides with another construction -たことがある, which takes precedence. なかったわけではない doesn't have the same problem.


Most people will read this as "I have never been unable to sing" (="I always could"). The other interpretation ("It's not that I couldn't sing"="I could to some extent") might not be impossible, but it would be much harder to read that way.

Whereas, the same doesn't happen when you change ないわけではない to なかったわけではない.


The only difference from the original sentence is that it describes a past event.

  • Thanks for the Insight! Indeed, as @naruto mentioned before, ことはない is a plain negation so whether ない・なかった comes before, it is a simple "plain" double-negation. To my estimation so far it seems like わけではない is more close to: "It's not that...". It's as if you are explaining or disagreeing with the other person's guess/estimation. In that case the Past-Sentence example puts things in their place clearly.
    – 悪戯猫
    Sep 27, 2022 at 18:47
  • As I see it, the main issue in what I argued is a conflict with another construction -たことがある. I edited my answer to clarify. Sep 28, 2022 at 9:25

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .