How many calories are you supposed to gain in one day?

A man between the ages of 19 and 30 with a sedentary lifestyle needs 2,400 calories; a more active male requires 200 more.

Females between the ages of 19 and 30 with a sedentary lifestyle require 2,000 calories per day; a more active lifestyle requires 200 more as well.

Add 10% to gain weight and 10% less to lose weight.