This is, for me, unverifiable information; hence this question.

Someone with a deeper knowledge of German than mine has recently told me that auf can also mean during, just like bei.

For instance, this person has told me that bei Tage(e) or bei Nacht can equally be rephrased as auf Tag(e) and auf Nacht, without losing its meaning.

However, my own research has turned no proof that this might be true.

Is it true?

  • 1
    South-German dialects: Auf d'Nacht trink i immer an Wein, dann kann i besser schlafn. Actually means before the night.
    – tofro
    Commented May 6, 2017 at 15:14

2 Answers 2


One thing I can imagine is that you mean something like:

in der Nacht von Montag auf Dienstag / in der Nacht auf Dienstag

This indeed means »during the night from monday to tuesday«.

»Auf Tag/Nacht« cannot mean »bei Tag/Nacht«, but can at least be used to describe a day/night partly:

Die Übergangsphase von Nacht auf Tag heißt Morgendämmerung.
(The transitional phase from night to day is called dawn.)

Die Übergangsphase von Tag auf Nacht heißt Abenddämmerung.
(The transitional phase from night to day is called dusk.)

However, »auf« can mean »during«.

Auf der Reise gab es viel zu sehen.
(There was a lot to see during the journey.)

  • And can Auf der Reise gab es viel zu sehen be rephrased as Bei der Reise gab es viel zu sehen? Commented May 6, 2017 at 15:14
  • Rule of thumb: you say Ich gehe auf eine Reise. Not zu. It's better to use auf in all occassions in that case. For those you can go both auf and zu, both auf and bei are okay. For those you can only go zu not auf, it's always bei.
    – Janka
    Commented May 6, 2017 at 15:52
  • @user26328: This would be unusual or even wrong. »Beim Reisen gab es viel zu sehen« is an alternative (second choice). Better: »Während der Reise ...«
    – Pollitzer
    Commented May 7, 2017 at 6:43
  • "Auf" in a timely sense usually discribes a transition. That can be from one day to another, from one place to another or past something. The specific points are not always necessary to include but you rather put an emphasis on what kind of transition it is.
    – Adwaenyth
    Commented May 8, 2017 at 13:47

Again, upon further study, I have discovered that auf and bei can both mean during (während), according to a most authoritative source.

Also, by all accounts, they do seem to be interchangeable when meaning during (während), at least according to this source, of which reputability I have for the time being absolutely no clue at all (except, perhaps, its being a German language learning site).

In conclusion, then, as far as these credible sources are concerned, and very much at variance with what Pollitzer told me earlier in the day, the generic »Während der Reise...« does seem in sooth to be fairly interchangeable with both »Bei der Reise...« and »Auf der Reise...«.

  • This doesn't really answer the question. *Auf Nacht is in nowhere near in meaning to "bei nacht". In fact, I'd call it entirely meaningless. Commented May 8, 2017 at 6:55

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.