Calorie Calculator
This calorie calculator can calculate how many calories are needed per day to maintain, lose, or gain weight. Learn about different types of calories and their effects on the human body.
Table of Contents
- Food Energy Converter
- Mifflin-St. Jeor Equation
- Revised Harris-Benedict Equation
- Katch-McArdle Formula
- Calculating Calories as a Weight Loss Tool
- Calorie "Zigzag" Cycling
- What Are Your Calorie Needs?
- What Is a Calorie?
- Calories in Everyday Foods
- Sample 2000, 1500, and 1200 Calorie Meal Plans
- Standard Calories Burned by Activities
- Food Sources That Provide Energy
You can use the calorie calculator to compute how many calories a person needs per day. It also provides simple advice for weight gain or weight loss.
Food Energy Converter
The following tool converts calories and other commonly used food energy units.
The conclusions of this calorie calculator depend on approximate averages and are based on many equations. The Harris-Benedict formula was one of the earliest formulas used to calculate basal metabolic rate (BMR) or the energy expended while at rest during a day. This formula was updated in 1984 to make it more reliable.
This formula was used until 1990 when the Mifflin-St. Jeor equation was established. Currently, the Mifflin-St. Jeor equation is considered the most accurate method for estimating basal metabolic rate.
The Katch-McArdle formula estimates resting daily energy expenditure (RDEE). It takes into account lean body mass, while the Mifflin-St. Jeor and Harris-Benedict equations ignore this factor.
The Mifflin-St. Jeor equation is the most accurate of these formulas for determining BMR. The Katch-McArdle formula is more accurate for lean individuals who know their body fat percentage.
The calculator uses the following three formulas:
Mifflin-St. Jeor Equation
| Gender |
Formula |
| Male |
BMR = 10W + 6.25H - 5A + 5 |
| Female |
BMR = 10W + 6.25H - 5A - 161 |
Revised Harris-Benedict Equation
| Gender |
Formula |
| Male |
BMR = 13.397W + 4.799H - 5.677A + 88.362 |
| Female |
BMR = 9.247W + 3.098H - 4.330A + 447.593 |
Katch-McArdle Formula
| Gender |
Formula |
| General |
BMR = 370 + 21.6(1 - F)W |
Where:
- W - body weight in kg
- H - body height in cm
- A - age
- F - body fat percentage
This result can estimate how many calories a person needs to consume in a day to maintain a constant weight. One pound of food or 0.45 kg is equivalent to approximately 3,500 calories.
People generally are not at rest all day. To estimate calories for maintaining weight more realistically, this number is multiplied by an activity factor (typically 1.2-1.95). This factor is based on a person's usual exercise level.
Experts recommend that to lose 1 pound per week, 500 calories should be reduced from the estimated daily caloric needs. For example, if a person needs 2,500 calories per day to maintain weight, consuming 2,000 calories per day during the week. In this case, they would lose 3500 calories or one pound of weight.
A combination of good nutrition and physical exercise is the best method for weight loss. We do not recommend reducing caloric intake by more than 1,000 calories per day. Losing more than 2 pounds per week can put the body in a dangerous condition and can slow down metabolism, quickly producing the opposite effect. Losing more than 2 pounds per week leads to a significant reduction in muscle mass, thereby lowering the basal metabolic rate. Remember, reduced muscle mass equals a lower basal metabolic rate.
If a person has an unhealthy diet, essential nutrients required by the human body will be deprived, which can have serious consequences. Dehydration can also cause rapid weight loss, which is very dangerous. Therefore, maintaining a nutrient-rich diet is crucial, especially during exercise and dieting. The body needs to maintain metabolic processes and restore itself.
Some experiments have shown that weight loss achieved through extreme hunger and dehydration can have counterproductive consequences. Lost weight tends to return in the form of fat, making a person's condition worse than before starting the diet. In addition to counting calories, attention must also be paid to the body's need for fiber and other nutrients.
Calculating Calories as a Weight Loss Tool
At the most basic level, we can divide the calorie counting weight loss method into several basic steps:
1. Use one of the following formulas to estimate your basal metabolic rate
If you know your body fat percentage, the Katch-McArdle formula can more accurately measure your basal metabolic rate. The results of these formulas are all estimates. Reducing 500 calories from your basal metabolic rate does not guarantee an accurate weight loss of 1 pound per week; it could be less or more.
2. Determine weight loss goals
Generally speaking, a caloric deficit of approximately 3500 calories roughly corresponds to a weight loss of one pound (about 0.45 kg). By consuming 500 fewer calories per day than the estimated basal metabolic rate, you can achieve a weekly weight loss of about 1 pound. If you want to lose weight more aggressively, consider reducing daily caloric intake by up to 1,000 calories.
However, losing more than 2 pounds per week may be harmful to health. If you hope to lose weight faster than this rate, we recommend consulting a healthcare professional or registered dietitian.
3. Determine a calorie counting strategy to achieve your goals
Many simple smartphone applications can help you record calories and activity levels. Most programs include estimated calorie counts for many branded meals or restaurant dishes.
They can predict calories based on the quantity of specific food ingredients. For many people, checking the size and weight of meals and calculating their caloric content can be quite troublesome. Therefore, like other methods, calorie counting is not suitable for everyone.
However, assuming you diligently measure and record the calorie counts of some regular meals, and you already know the caloric levels of these meals. In this case, predicting caloric intake becomes easier, and you don't need to weigh or evaluate food every time. Some websites can also provide help. Additionally, using Excel spreadsheets or paper diaries is also a reasonable alternative.
4. Recognize that weight loss is not the only aspect of health and fitness to consider
You need to consider the loss or gain of fat versus muscle. Monitor your performance over time, and if necessary, make adjustments to better achieve your goals.
Due to variations in water intake or time of day, weight can fluctuate significantly. It's best to collect measurement data over a longer period, such as a week. Additionally, it's best to perform measurements under consistent conditions, such as weighing first thing in the morning before breakfast, rather than at random intervals throughout the day.
Calorie "Zigzag" Cycling
Calorie "zigzag" cycling is a popular dieting strategy where you consume fewer calories on some days and more calories on other days. This strategy can help prevent your metabolism from slowing down in response to consistently low calorie intake.
What Are Your Calorie Needs?
Everyone's calorie needs are different, depending on several factors:
- Age
- Gender
- Weight
- Height
- Activity level
- Goals (weight loss, weight gain, or weight maintenance)
Our calorie calculator calculates your personalized calorie needs based on these factors.
What Is a Calorie?
A calorie is a unit of energy used to measure the energy stored in food. Our bodies need calories to perform basic functions like breathing, blood circulation, and cell repair, as well as to perform physical activities.
Calories in Everyday Foods
Here are the calorie contents of some common foods:
- One medium apple: about 95 calories
- One slice of bread: about 80 calories
- One cup of milk: about 100 calories
- One egg: about 70 calories
- One cup of rice: about 200 calories
- 100 grams of chicken: about 165 calories
Sample 2000, 1500, and 1200 Calorie Meal Plans
2000-Calorie Meal Plan (Weight Maintenance)
- Breakfast: Oatmeal with fruit and nuts (about 400 calories)
- Morning snack: One apple (about 95 calories)
- Lunch: Grilled chicken breast with vegetable salad and brown rice (about 500 calories)
- Afternoon snack: Yogurt (about 150 calories)
- Dinner: Grilled fish with steamed vegetables and sweet potato (about 600 calories)
- Evening snack: A handful of nuts (about 250 calories)
1500-Calorie Meal Plan (Weight Loss)
- Breakfast: Protein smoothie (about 300 calories)
- Morning snack: Half an apple (about 50 calories)
- Lunch: Vegetable soup with a small amount of chicken and bread (about 400 calories)
- Afternoon snack: Carrot sticks (about 25 calories)
- Dinner: Grilled fish with plenty of vegetables (about 500 calories)
- Evening snack: Sugar-free yogurt (about 100 calories)
1200-Calorie Meal Plan (Rapid Weight Loss)
- Breakfast: Boiled eggs and vegetables (about 250 calories)
- Morning snack: Cucumber slices (about 10 calories)
- Lunch: Vegetable salad with a small amount of chicken (about 300 calories)
- Afternoon snack: Cherry tomatoes (about 25 calories)
- Dinner: Steamed vegetables with a small amount of protein (about 400 calories)
- Evening snack: Sugar-free gelatin (about 50 calories)
Standard Calories Burned by Activities
Here are the calories burned per hour by some common activities (for a 155-pound adult):
- Walking (3.5 mph): about 280 calories
- Running (5 mph): about 590 calories
- Bicycling (12-14 mph): about 570 calories
- Swimming (moderate intensity): about 450 calories
- Yoga: about 180 calories
- Strength training: about 220 calories
Food Sources That Provide Energy
A healthy, balanced diet should include these three macronutrients:
- Carbohydrates (provide 4 calories per gram)
- Protein (provide 4 calories per gram)
- Fat (provide 9 calories per gram)
Choosing nutrient-rich foods like whole grains, lean proteins, healthy fats, and a variety of fruits and vegetables can ensure you get the energy and nutrients you need.