Article 72 of the Indian constitution deals with the pardoning power of president which says that President of India has the power to grant mercy in certain criminal cases. President has the power :
Pardon
Commutation
Remission
Respite
Reprive
The President can use these powers:

In cases where punishment is by a court-martial, For offences against Union laws, and In death sentence cases, regardless of the law under which the conviction occurred. Yes, judicial review of the President’s mercy powers is allowed, but only to a limited extent.