don't you think?; is it?; I wonder
Polite sentence-ending expression that turns a statement into a question, often seeking agreement or confirmation. Equivalent to だろうか in plain form.
See also: だろうか
Do you think it will rain tomorrow?
I wonder if this dish is tasty.
かな is a casual way to voice wondering or a soft question, while でしょうか is the polite equivalent used in formal speech or with strangers.
でしょうか is the polite, formal way to voice the same kind of tentative question that かしら expresses casually.
だろうか is the plain/casual form for wondering aloud, while でしょうか is its polite counterpart used in formal speech or when addressing others respectfully.
Polite form of だろうか, from です (polite copula) + う (volitional) + か (question particle).