How do you say 'tonight' in Hindi?

How do you say 'tonight' in Hindi?

आज रात - Āja rāta

Can we also say आज रात को - Āja rāta ko?

आज रात को can be used depending on the context. In general it is an incomplete sentence, and can be used when answering to a question as "when is the function" and one would said "tonight". in such cases also, आज रात is more apt. one would use आज रात को when notifying someone of something happening tonight as "there is a function tonight"- आज रात को त्योहार है