Explanation:

Section 7 in The Payment of Gratuity Act, 1972
Determination of the amount of gratuity.—
(1) A person who is eligible for payment of gratuity under this Act or any person authorised, in writing to act on his behalf shall send a written application to the employer, within such time and in such form, as may be prescribed, for payment of such gratuity.
(2) As soon as gratuity becomes payable, the employer shall, whether an application referred to in sub-section (1) has been made or not, determine the amount of gratuity and give notice in writing to the person to whom the gratuity is payable and also to the controlling authority specifying the amount of gratuity so determined.
(3) The employer shall arrange to pay the amount of gratuity within thirty days from the date it becomes payable to the person to whom the gratuity is payable.