You can use a weight gain goal calculator to understand how many calories you need per day to gain the optimal amount of weight.

This depends on your health and fitness goals, current weight and existing health conditions. Speak to your nutritionist to out together the right calorie intake calculator to gain weight. 

This depends on your current weight and metabolic rate. It’s best to consult your nutritionist to put together a calorie calculator for weight gain to reach your goals. Generally, the range is between 300-500 calories more if you want to gain weight slowly, and 700-1000 calories more if you want to gain weight quickly. 

A balanced diet with healthy fats, proteins, carbohydrates and fibre will help you gain weight. Lean meat and eggs help in weight gain - you can use a protein calculator for weight gain to figure out how much protein you need in a day. You can also include milk, paneer, rice, nuts and nut butters, potatoes, sweet potatoes, protein powders and oily fish like salmon and mackerel.