Weight Gain Calculator

Time Span Choose Date

Calorie Needed To Gain Weight:
_____ Calories/day

Weight Gain ParametersValue
Current Weight
Goal Weight
Goal Time (In days)
To Maintain Weight (calorie/day)
Calorie Surplus (calorie/day)

Weight gain is a common goal for many people, whether it’s to gain muscle or improve health. However, it can be challenging to determine the optimal weight gain and calorie intake. That’s where weight gain calculators come in.

Weight gain calories calculator tells you how many calories you need to eat to gain the weight you want.

What Is Weight Gain?

Weight gain refers to an increase in body weight due to an increase in the amount of body fat or muscle mass. It is a natural phenomenon that occurs when the number of calories consumed exceeds the number of calories burned by the body. This excess energy is stored in the body as fat or used to build muscle.

  • To achieve a slow weight gain, you should aim for a surplus of 300–500 calories above your maintenance level.
  • To gain weight fast, you should try to eat an extra 700-1,000 calories a day.

Gaining weight can be good for some people, like those who want to gain muscle and get stronger or recover from illness. But for others, it can be bad if they eat unhealthy food or spend too much time sitting still.

It’s important to understand the factors that lead to weight gain and make smart decisions about how to get a healthy weight.

It is important to note that calorie calculators offer approximations, as your calorie needs may fluctuate by several calories per day.

You don’t have to monitor how many calories you eat for the rest of your life, but doing so for the first few days or weeks could help you figure out how many calories you’re eating.

Healthy Weight Gain
Related Calculator: Weight Loss Calculator

How To Calculate Calories Needed To Gain Weight

1. Determine Your BMR

Use an online BMR calculator or the Mifflin-St Jeor Equation to estimate your BMR based on your age, gender, weight, and height.

  • For men: BMR = (10 x weight in kg) + (6.25 x height in cm) – (5 x age in years) + 5
  • For women: BMR = (10 x weight in kg) + (6.25 x height in cm) – (5 x age in years) – 161

2. Estimate Your Activity Level

Based on your daily routine and exercise habits, you should estimate how many calories you burn through physical activity.

There are several ways to do this, but a common method is to use an activity multiplier:

Activity Level

  • Sedentary (little or no exercise): BMR x 1.2
  • Lightly active (1-3 days of exercise per week): BMR x 1.375
  • Moderately active (3-5 days of exercise per week): BMR x 1.55
  • Very active (6-7 days of exercise per week): BMR x 1.725
  • Extra active (very intense exercise or physical job): BMR x 1.9

3. Calculate Your TDEE:

  • TDEE = BMR + Activity Level

4. Calculator Calories For Weight Gain

Once you have calculated your TDEE, you can adjust your calorie intake to achieve your desired weight gain.

  • To gain weight, you must create a calorie surplus by consuming more calories than your TDEE. A daily surplus of 500–1000 calories is recommended for safe and sustainable weight gain.
  • Keep track of your calorie intake and make gradual changes to ensure you are on track towards your goal.
  • 1 kg of body fat contains approximately, 7700 calories.
  • 1 pound of body fat contains approximately, 3500 calories.

Calories Required To Gain Weight

To Gain Weight 0.25 Kg/Week

  • = (0.25 kg x 7700 calories/kg ÷ 7 days/week).
  • You need a 275-calorie surplus per day.
  • If your TDEE is 2000 calories per day, you should consume 2275 calories per day (2000 + 275) to gain 0.25 kg/week.

To Gain Weight 0.5 Kg/Week

  • = (0.5 × 7700 ÷ 7).
  • You need a 550-calorie surplus per day.
  • If your TDEE is 2000 calories per day, you should consume 1450 calories per day (2000 + 550) to gain 0.5 kg/week.

To Gain Weight, 1 Kg/Week

  • = (1 × 7700 ÷ 7).
  • You require an 1100-calorie surplus per day.
  • If your TDEE is 2000 calories per day, you should consume 3100 calories per day (2000 + 1100) to gain 1 kg/week.

5. Calculate Zig Zag Calories

To calculate Zigzag calories, you’ll need to determine your weekly calorie target and then alternate between high and low-calorie days to meet that target.

  • Determine your weekly calorie target based on your weight gain.
  • Daily Calorie Target = Weekly Calorie Target / 7
  • Alternate between low and high calorie days to create a calorie surplus for weight gain.
  • On low calorie days, consume 300–500 calories less than your daily target,
  • On high calorie days, consume 100–300 calories more than your daily target.

6. Track Your Calories

Select a method for tracking your calories and progress towards your weight gain goals. Several user-friendly applications are available on smartphones that enable you to monitor your calorie intake, exercise, and progress.

Counting calories may not suit everyone, as it can be challenging to gauge food proportions and the number of calories they contain. However, by tracking and measuring the calorie content of some of your regular meals, you can quickly learn to estimate calorie intake without weighing or measuring your food each time.

Alternatively, you may prefer to manually track your progress using an Excel spreadsheet or a pen and paper journal, both of which are viable options.

7. Track Your Progress

Take time to track your progress and adjust your plan accordingly. You should not only consider weight gain when deciding your health and fitness; you should also consider muscle gain.

Furthermore, measurements should be taken over longer periods of time, such as a week (rather than daily), as significant variations in weight can occur simply based on water intake or time of day.

For consistent measurements, weigh yourself every day at the same time, like right after you wake up and before breakfast.


It’s important to note that achieving a healthy weight gain requires a proper diet and regular exercise. It may be tempting to increase your calorie intake drastically to gain weight quickly, but it is not recommended.

Gaining weight too quickly can have negative effects on your body. Aiming to gain 1 pound (0.45 kg) a week would mean adding roughly 500 calories to your daily weight maintenance calorie needs.

It’s important to maintain a healthy diet while increasing calorie intake to support the body’s metabolic processes and replenish itself.

Therefore, it’s important to monitor both calorie and nutrient intake, including fiber, to ensure the body receives all necessary nutrients to maintain balance and overall health. If you’re gaining weight at a rate of 1 pound (0.45 kg) or more per week, it’s important to consult with a doctor.

Calories Require To Gain Weight

Mifflin-St. Jeor Equation To Calculate Weight Gain Calories

Let’s say a 40-year-old female weighs 70 kilograms (154 pounds) and is 170 centimeters (5 feet 7 inches) tall.

To calculate her estimated BMR using the Mifflin-St. Jeor equation, we need to use the following formula:

  • BMR = (10 x weight in kg) + (6.25 x height in cm) – (5 x age in years) – 161

Substituting the values into the equation, to get BMR:

  • = (10 x 70) + (6.25 x 170) – (5 x 40) – 161
  • = 700 + 1062.5 – 200 – 161
  • = 1,401.5 calories per day

TDEE for Lightly active (1-3 days of exercise per week): BMR x 1.375

  • TDEE =1401.5 x 1.375
  • TDEE = 1927.06

This is the total calories you could eat every day if you wanted to maintain your weight.

To Gain Weight 0.25 Kg/Week

  • = (0.25 kg x 7700 calories/kg ÷ 7 days/week).
  • She needs a 275-calorie surplus per day.
  • Calories for weight gain = TDEE +275.
  • = 2202

Zigzag Calorie Cycling To Gain Weight

Zigzag calorie cycling isn’t just for weight loss. In fact, it can also be an effective strategy for those looking to gain weight. By alternating between high and low-calorie days, you can meet your weekly calorie target and avoid the adaptation that comes with a consistent high-calorie intake.

To implement zigzag calorie cycling for weight gain, a person would alternate between high and low-calorie days, aiming to meet the same weekly calorie target.

For example, someone with a weekly calorie target of 18,500

Zig Zag Plan-1

  • Consume 3,500 calories for three days a week and
  • 2,000 calories for the other four days.

Zig Zag Plan-2

  • Consume 2,500 calories each day for five days a week and
  • 3,000 calories for the other two days.

This approach not only provides flexibility in the diet, but also allows for planned overeating on special occasions without derailing progress. By consuming fewer calories on low-calorie days, a person can balance out the excess calories consumed on high-calorie days.

When implementing zigzag calorie cycling for weight gain, it’s essential to ensure that the high-calorie days provide enough calories to support muscle growth and recovery. The high-calorie days should be tailored to meet the body’s demands, especially for those with a higher activity level.

While there is no concrete rule on how to vary calorie intake with zigzag calorie cycling, a general recommendation is to very high and low-calorie days by approximately 200–300 calories.

The calculator provides two zigzag diet schedules, one with two high-calorie days and five low-calorie days, and one that gradually increases and reduces calories. However, the approach should be personalized based on individual preferences and lifestyle.

The key to success with zigzag calorie cycling for weight gain is consistency and sticking to the plan. You can get the results you want by finding an approach that works for you and sticking to it.

How To Calculate Zigzag Calorie Cycling For Weight Gain

  • Daily Calorie Target (Weight Gain) = Weekly Calorie Target / 7
  • Plan low calorie days when you consume 100–300 calories less than your daily calorie target.
    • Low Calorie Day Target = Daily Calorie Target – (100-300) calories.
  • Plan high calorie days when you consume 100–300 calories more than your daily calorie target.
    • High Calorie Day Target = Daily Calorie Target + (100-300) calories
  • Create a schedule for your low and high calorie days, and stick to it consistently.
    • Example: Monday – Low Calorie Day
    • Tuesday – High Calorie Day
    • Wednesday – Low Calorie Day, and so on.
  • Monitor your progress by regularly weighing yourself and taking body measurements. Adjust your calorie intake as needed based on your progress.
    • If your progress is slower than expected, you can reduce your calorie intake on high calorie days or increase your calories on low calorie days.
    • If your progress is faster than expected, you may need to decrease your calorie intake on high calorie days or decrease your calories on low calorie days.
  • Remember to maintain a balanced and nutritious diet, regardless of the calorie intake on a given day. It’s important to consume a variety of nutrient-dense foods to support your overall health and well-being.

Other Formulas For Calculating Weight Gain Calories

There are several formulas that can be used to calculate calories to gain weight.

  1. Harris-Benedict equation
  2. Katch-McArdle equation
  3. Cunningham equation
  4. Owen equation

How Many Calories Do You Need?

A good daily caloric intake is important for gaining weight. However, there is no one-size-fits-all answer to the question of how many calories a person needs to gain weight in a healthy manner. Many factors, such as age, weight, height, sex, level of physical activity, and overall health, play a role.

For example, a young athlete who engages in vigorous exercise for many hours each day will require more calories than a sedentary office worker of the same age and gender. The athlete’s body will need more energy to sustain the physical demands of their sport and maintain optimal health, while the office worker’s body will require fewer calories to maintain basic bodily functions.

The total number of calories a person requires each day varies depending on many factors, including the person’s age, sex, height, weight, and level of physical activity. In addition, a need to lose weight, maintain, or gain weight and other factors affect how many calories should be consumed.

According to the 2015-2020 Dietary Guidelines for Americans, daily calorie requirements for weight gain may range from 2,000 to 3,000 calories for men and 1,600 to 2,400 calories for women.

Within each age and sex category, the low end of the range is for sedentary individuals; the high end of the range is for active individuals

Generally, a healthy weight gain is between 0.5 and 1 pound per week, which would mean that you would need to eat an extra 250 to 500 calories per day.

How Many Calories Do You Need

How Many Calories Do I Need To Gain Weight?

To gain weight, you must consume more calories than your total energy expenditure. Your total daily energy expenditure (TDEE) is determined by several factors, including your basal metabolism, metabolic response to food, physical activity, and physiological state such as growth, pregnancy, or lactation.

  • You can calculate your basal metabolism using the Mifflin-St. Jeor equation in a BMR calculator
  • Then know your maintenance calories by adding activity level with BMR.
  • Once you have determined your daily caloric needs, you need to consume excess calories to gain weight.
  • Typically, you require approximately, 3850 kcal to gain 0.5 kg or 1.1 lbs in a week.
  • This means that consuming an additional 550 kcal every day should result in a weight gain of 0.5 kg (1.1 lbs) within a week.

If you haven’t already, have a look at our weight gain calorie calculator. It estimates your daily energy expenditure, giving you a more profound understanding of how many calories you need to consume per day to gain weight.

Give it a try to jumpstart your weight gain journey.

Calculate Your Daily Calories Requirement

Many people have a hard time figuring out how many calories they require daily and making a diet plan that meets those needs. This is where our Weight Gain Calculator is beneficial.

Our user-friendly tool is designed to help anyone to look to gain weight. It calculates your daily and weekly calorie requirements and estimates how long it will take to achieve your weight gain goals in a healthy and safe manner.

This tool is ideal for anyone who wants to gain weight in a structured way, ensuring that they are consuming enough calories to achieve their goals without compromising their health.

Main Sources Of Calories

Carbohydrates, proteins, and fat are the three macronutrients that constitute the majority of calories in the diet.

1. Carbohydrates

Carbohydrates are the body’s primary source of energy and can be found in foods like grains, fruits, vegetables, and dairy products.

They come in two forms: simple and complex.

  • Simple carbohydrates are quickly digested and provide a quick burst of energy
  • Complex carbohydrates take longer to digest and provide a more sustained source of energy.

2. Protein

Proteins are essential for building and repairing tissues in the body and are found in foods like meat, fish, poultry, eggs, and beans.

They are made up of amino acids, which the body uses to build and maintain muscles, organs, and other tissues.

3. Fat

Fat is also a source of energy and is found in foods like meat, dairy products, nuts, seeds, and oils. There are different types of fat, including saturated, unsaturated, and trans fat.

Unsaturated fats, like those found in olive oil, avocados, and nuts, are considered healthier than saturated and trans fats, which are found in processed foods, fried foods, and baked goods.

Main Sources of Calories

Calories In Common Food Components

Food ComponentEnergy per Gram
Carbohydrates4 calories/gram
Protein4 calories/gram
Fat9 calories/gram

Macronutrient Ratios For Weight Gain

If your goal is to gain lean muscle mass, it is recommended to consume a higher proportion of your calories from protein. Mike Roussell, recommends the following baseline macronutrient ratios.

Note that these ratios are based on the overall percentage of calories consumed.

Body TypeFat %Carbohydrate %Protein %
Ectomorph (skinny)20-30%50-60%20-30%
Mesomorph (muscular & athletic)15-25%40-50%30-40%
Endomorph (broad & thick)25-35%30-40%30-40%

It is important to note that the ratios presented are general guidelines and may require adjustment based on your specific needs and objectives.


What Are The Risks Of Being Underweight?

The clinical definition of underweight is having a body mass index (BMI) below 18.5. This is estimated to be less than the body mass needed to sustain optimal health.

Being underweight can also increase the risk of several health problems, including:

1. Malnutrition

Being underweight can be a sign of malnutrition, which can lead to deficiencies in essential nutrients such as protein, vitamins, and minerals.

2. Weakened Immune System

Malnutrition can weaken the immune system, making it difficult for the body to fight off infections and illnesses. A study has shown that being underweight can affect your immune system, which can make you more likely to get sick.

3. Anemia

Malnutrition can lead to a lack of iron and other essential nutrients needed to produce red blood cells, resulting in anemia and its associated symptoms.

4. Osteoporosis

A low BMI can increase the risk of getting osteoporosis and other bone-related problems because a low body weight can lead to a loss of bone density.

5. Reproductive Problems

Being underweight can affect hormone levels and lead to reproductive problems, including irregular periods and infertility.

6. Growth And Development Issues

Being underweight can have a negative impact on growth and development, especially in children and adolescents.

These health risks can be reduced by maintaining a healthy weight through a balanced diet and regular exercise.

How To Gain Weight And Build Muscle

To gain weight, you must create a calorie surplus, which means consuming more calories than your TDEE. Here are some ways to use TDEE to gain weight:

1. Calculate Your Weight Gain Calories

Start by using an online calculator or a formula to figure out how many calories you need to gain weight. This will give you an idea of how many calories your body needs to gain weight.

2. Increase Your Caloric Intake

The most important thing you can do to gain weight is to create a calorie surplus, which means you eat more calories than your body needs.

Aim to add around 500 calories to your daily diet, which should help you gain around 1 pound (0.45 kg) per week.

It is important to note that eating a calorie surplus does not mean eating junk food all day long. You still need to eat healthy foods that will provide your body with the nutrients it needs.

3. Choose Healthy, High-Calorie Foods

Eating nutritious foods that are high in calories is a good way to gain weight. It is important to eat plenty of high carb and high fat foods to gain weight. It is also important to eat plenty of protein at each meal, as protein helps to build muscle.

Focus on eating nutrient-dense, high-calorie foods such as nuts, avocados, whole grains, lean protein, and healthy fats. Avoid filling up on empty calories such as sugary drinks and junk food.

4. Increase Your Protein Intake

Protein is essential for optimal growth, development, and human health. Adequate consumption of high quality proteins from animal products is especially important for people who are trying to gain weight.

A 2020 study found that increasing protein intake can lead to increased lean muscle mass. The recommended dietary allowance of protein for healthy adults is between 1 to 1.6 grams per kilogram of body weight per day. However, up to 2 grams per kilogram of body weight per day may be safe for healthy adults.

High protein foods include meats, fish, eggs, some dairy products, legumes, nuts, and others. Protein supplements like whey protein can also be useful if it is difficult to get enough protein in your diet.

5. Eat frequently

Eating frequently is one of the best ways to gain weight. This is because it helps you spread out your calories throughout the day, which can make it easier to reach your daily goal.

When you eat less frequently, your body goes into starvation mode and it becomes harder to gain weight. Aim for 3–4 meals per day, with 1–2 snacks in between.

Tips for eating frequently:

  1. Plan Ahead: Prepare snacks and meals in advance, so you always have something nutritious available.
  2. Small and Balanced: Opt for smaller, balanced meals and snacks. Include a mix of protein, healthy fats, and carbohydrates for sustained energy.
  3. Snack Options: Keep healthy snack options on hand, such as nuts, fruits, yogurt, whole-grain crackers, or veggies with hummus.
  4. Timed Meals: Aim to eat every 3-4 hours to maintain a consistent eating schedule.
  5. Avoid Processed Snacks: Opt for whole, nutrient-dense foods instead of processed and sugary snacks.
  6. Include Protein: Include protein-rich snacks like Greek yogurt, cottage cheese, or a protein shake to support muscle growth.

6. Start Weight Lifting

Resistance training leads to muscle hypertrophy, which increases muscle mass. At least 4-5 times per week, aim to lift weights or perform bodyweight exercises.

Prioritize compound exercises that work multiple muscle groups at once. Squats, deadlifts, bench press, overhead press, rows, and pull-ups are excellent choices. The push up, pull up and other compound exercises really help to put muscle mass during my muscle building journey.

7. Get Enough Sleep

A study has found that sleep deprivation can lead to a decrease in testosterone levels and can impair muscle gain.

Sleeping is a crucial factor in promoting weight gain, as during sleep, the body goes through a process of repairing and rebuilding muscle tissue. This is very important after doing heavy lifting or other hard exercises.

When you get enough sleep, you can lift heavier weights and do harder workouts later on.

This study showed the relationship between sleep deprivation and insulin resistance. The researchers found that sleep deprivation is associated with decreased insulin sensitivity, which means that the body is less able to use glucose for energy.

Tips To maximize the benefits of sleep for weight gain:

  • Aim for 7-9 hours of quality sleep each night.
  • Establish a consistent sleep schedule, going to bed and waking up at the same time daily.
  • Create a relaxing bedtime routine to signal your body that it’s time to wind down.
  • Ensure your sleep environment is comfortable, cool, dark, and quiet.
  • Limit caffeine and avoid heavy meals close to bedtime.

8. Be Consistent

Consistency is key when it comes to weight gain. Make sure you’re consuming enough calories every day and staying active to build muscle mass.

Whether it pertains to improving your weight lifting performance, enhancing your lifting capacity, or improving your dietary habits, modest and consistent efforts can yield significant outcomes.


How can I gain weight in a healthy way?

To gain weight in a healthy way, it is recommended to increase calorie intake gradually and focus on consuming nutrient-dense foods such as lean protein, whole grains, fruits, and vegetables.

Resistance training can also be helpful in building muscle mass.

How much weight can I realistically expect to gain per week?

A healthy weight gain is between 0.5 and 1 pound per week. This can vary based on individual factors such as age, gender, height, weight, and level of physical activity.

How do you calculate weight gain?

To calculate weight gain, you need to determine the total caloric surplus required to achieve your weight goal. To promote weight gain, you need to calculate your total daily caloric needs and then add an appropriate surplus of calories. The formula generally considers factors such as age, gender, height, current weight, activity level, and weight gain goals.

How much does it take to gain 1 kg?

It takes about 7,700 calories to gain 1 kg of body weight. This means that if you eat 7,700 calories more than you burn each week, you will gain about 1 kg of weight.

If you are trying to gain weight, it is important to eat a healthy diet that is rich in calories. You should also make sure to exercise regularly, as this will help you build muscle.

Can I gain 5 kg in a month?

It is possible to gain 5 kg in a month, but it is not recommended. The rapid gain of weight can result in health issues such as obesity, heart disease, and diabetes.

A safe and healthy rate of weight gain is 1-2 pounds (0.45-0.91 kg) per week. This means that you would gain about 5 kg in 12 weeks, or 3 months.

How many kg should I gain?

A good starting point is to aim to gain 1-2 pounds (0.45-0.91 kg) per week. It is also important to be patient and realistic when trying to gain weight. It takes time to see results, so don’t get discouraged if you don’t see changes immediately.

How can a skinny person gain weight fast?

  1. Increasing Caloric Intake: Consume more calories than your body burns to create a caloric surplus, which promotes weight gain.
  2. Nutrient-Dense Foods: Focus on nutritious, calorie-dense foods such as nuts, avocados, whole grains, and healthy fats.
  3. Protein-Rich Diet: Add protein sources like eggs, lean meats, fish, and legumes to support muscle growth.
  4. Strength Training: It stimulates muscle growth and adds lean mass to your body.
  5. Frequent Meals: Eat several small, balanced meals throughout the day to maintain a steady calorie intake.
  6. Avoid Excessive Cardio: Limit excessive cardio workouts, as they burn calories and may hinder weight gain efforts.
  7. Stay Hydrated: Drink enough water to support overall health and proper digestion.
  8. Get Adequate Rest: Allow your body to recover and grow by getting sufficient sleep each night.

What is the maximum weight gain per month?

The maximum safe weight gain per month is 2 pounds (0.91 kg) for women and 3 pounds (1.36 kg) for men. Any more than this and you are at risk of gaining too much fat, which can lead to health problems.

Rapid weight gain beyond this range can be unhealthy and may lead to issues like metabolic disturbances or nutrient imbalances. It is essential to focus on gradual and sustainable weight gain for long-term health and well-being.


To gain weight, you need to consume more calories than you burn. The Weight Gain Calculator is a useful tool that can help you determine your TDEE and estimate the number of calories you need to consume to reach your weight gain goals.

It’s important to consume a balanced diet with a proper ratio of macronutrients, including protein, carbs, and fats, to support muscle growth and overall health.

You should aim to gain weight gradually and in a healthy way, rather than trying to gain weight too quickly, which can lead to negative health effects.


  1. How much protein you need everyday? Harvard Health Publishing, Harvard Medical School. https://www.health.harvard.edu/blog/how-much-protein-do-you-need-every-day-201506188096
  2. U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015 – 2020 Dietary Guidelines for Americans. 8th Edition. December 2015.
  3. Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. “A new predictive equation for resting energy expenditure in healthy individuals“ The American Journal of Clinical Nutrition (February 1990).
  4. Prevalence of Underweight Among Adults Aged 20 and Over: United States, 1960–1962 Through 2017–2018.
  5. Nathaniel F Watson, Kathryn Paige Harden, Dedra Buchwald, Michael V Vitiello, Allan I Pack, David S Weigle, Jack Goldberg Sleep duration and body mass index in twins: a gene-environment interaction.

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