Я не собиралась говорить ей, и она ни за что бы не догадалась.
Я не собиралась говорить ей, и она нипочем бы не догадалась.
In my experience, I seem to come across "ни за что" ten times more often. How are they nuanced?
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Sign up to join this communityЯ не собиралась говорить ей, и она ни за что бы не догадалась.
Я не собиралась говорить ей, и она нипочем бы не догадалась.
In my experience, I seem to come across "ни за что" ten times more often. How are they nuanced?
"нипочем" - in this case I would translate it as "no way" (no way guessed) - in contrary to "ни за что" (in this case I would translate it as "never") is most often used by villagers or in folk tales.
I would recommend in most cases to use "ни за что" in such contexts.
"Нипочём" (is the meaning of "never") is more colloquial than "ни за что". The latter can be used in any situation, while the former - only in informal speech (or literature stressing the informality);
Also note that "нипочём" has multiple meanings.
"Нипочём," apart from being equivalent to "ни за что," actually also has at least two well-known meanings that can never be substituted by "ни за что." Apart from that of "no way" already mentioned in @IvanOlshansky's answer, it can also mean being unharmed, as in "ему все горести нипочём."
I also want to stress that while "нипочём" indeed means "no way," you shouldn't think of it as an exact equivalent. You can use "no way" as a separate phrase in English. You cannot use "нипочём" as a stand-alone, self-sufficient word. This holds true in the case of "ни за что" / "нипочём" as well.
Compare two examples:
The first is perfectly valid, but the second does not make any sense at all. So as a substitute for "ни за что," you can only use it in conjunction with a "не" + verb construction.
"ни за что" means "never". "нипочём" means "easy to do".
examples: "Я ни за что это не сделаю" - I will never do that. "Мне это нипочём" - I can easily do that.
sentence "Я не собиралась говорить ей, и она нипочем бы не догадалась" make no sence.