を問(と)わずRegardless of, Whether or not, No matter, With or without

を問(と)わず is a pattern which makes use of the special-class う-Verb 問(と)う 'to inquire' and the literary auxiliary verb ず, which connects with verbs in the same way, and carries the same meaning as ない. While the literal meaning of this grammar structure is 'without questioning (A), (B)', it is used more as a formal way to express 'regardless of (A), (B)', 'whether (A) or not, (B)', or 'with or without (A)', (B)'.

This structure is seen almost exclusively after nouns, but can also follow structures like か, or かどうか that are modifying adjectives. を will mark the 'question' which is 'not being asked'.

Occasionally, は will replace を at the beginning of 問わず. This puts further emphasis on contrast, and slightly strengthens the phrase overall.

Caution

Although を問(と)わず may be thought of as similar to 'regardless', there are actually situations where the nuance is closer to 'in any case for (A), (B)'. This is particularly true when (A) is being expressed as a scope. Let's compare を問(と)わず to に関(かか)わらず to see the difference.