Under section 125 of CrPC, a wife can claim for maintenance under set conditions, such as if the wife doesn't have a regular income, and if the man is well off, he must pay maintenance to his wife, children and parents. The maintenance amount is not a pre decided amount, it depends on your income and what the court decides.
Keep in mind, that if your wife is a working person, she can't claim maintenance as one of the requirements to claim maintenance is that the person who is claiming must be non working, and doesn't have means to sustenance. The maintenance laws differ with religion, as each religion has it's own laws regarding maintenance.
Under the various maintenance laws in India, it can be deferred that maintenance after divorce is granted to the wife only on the following grounds:
If the husband has abandoned her or neglected her on his own will
If the husband has tortured her or subjected her to cruel treatment
If the husband is suffering from a virulent or venereal disease
If the husband is living with another wife
If the husband has a concubine which he keeps in the same residence where his wife lives, or he lives with the concubine at some other place.
If the husband has changed his religion to any other religion.
Any other reason that is justifiable for living in separation with her husband.
Under Bhagwan Dutt v. Kamla Devi, (1975) 2 SCC 386- it was decided that women's income will be taken into consideration while determining the amount of maintenance payable to her, and it was also decided that it's not an absolute right of a wife who has been neglected to claim maintenance, nor is it a liability for the husband to support her at all times.
Hope this helped!