Calorie Calculator: How Many Calories Do You Need? (2024)

The Forbes Health Calorie Calculator estimates the number of calories your body uses each day. If you want to lose weight, it calculates the number of daily calories you need to consume to achieve your weight loss goal. It also displays how long it will take you to reach your goal weight safely.

Calculating Daily Calories To Maintain Weight

To calculate your daily calorie needs to maintain your weight, the calculator considers your:

1. Resting metabolic rate (RMR)
2. Physical activity
3. The thermogenic effect of food (the calories you burn while processing food)

Each of these components requires a different amount of calories.

1. Your RMR requires the most energy, far more than physical activity or food processing. It can be measured scientifically in a lab or estimated using an equation. In this calculator, your RMR is measured using the Mifflin-St Jeor equation. It’s the most reliable formula, according to a review of studies in the Journal of the American Dietetic Association. It calculates your RMR based on your sex, weight, height and age.

2. Physical activity burns calories, so athletes need to consume more calories than people who don’t exercise. An activity factor—ranging from 1.2 for people who are sedentary to 1.9 for extremely active people—is assigned based on your physical activity level. The calculator then multiplies your RMR by this number.

3. The thermogenic effect of food makes up the remainder of your daily energy needs (approximately 10%). To find this number, the calculator takes your RMR multiplied by your activity factor and multiplies that number by 10%.

Calculating Daily Calories To Lose Weight

To determine your daily calorie needs to lose weight, the calculator decreases the number of calories you use each day by 25%, resulting in a new recommended daily calorie intake. Our Forbes Health Calorie Calculator panel of experts recommended this equation for safe, sustainable weight loss.

The calculator won’t display fewer than 1,200 calories a day no matter your starting weight. “If you go below that, it’s very difficult to get all the macronutrients and micronutrients you need for optimal health,” says Melina Jampolis, M.D., a Forbes Health Advisory Board member.

The Forbes Health editorial team consulted Forbes Health Advisory Board members Melina Jampolis, M.D., Toby Amidor, R.D. and Sabrena Jo, M.S., the senior director of science and research at the American Council on Exercise (ACE), for this calculator. They reviewed the methods used by this tool to calculate daily calorie needs to maintain and lose weight.

The number of calories you should eat or drink a day depends on several things—your age, sex, height, weight and physical activity. In general, men require more calories than women, and because metabolism slows as people age, older adults generally need fewer calories than younger people.

While a calorie calculator gives you the best approximation of your needs, the government’s Dietary Guidelines for Americans, 2020-2025 offers estimates.

Estimated Daily Calorie Needs Chart

Source: Dietary Guidelines for Americans, 2020-2025

A calorie deficit occurs when a person consumes less calories than their total daily energy expenditure, which may result in weight loss. However, spending too long of a period in this deficit state may create a situation where your body becomes used to the lower energy intake, leading to metabolic adaptation or the “plateau effect.” This may cause weight loss to slow, or “plateau.”

What is the Minimum Amount of Calories Needed Daily?

Women should consume no less than 1,200 calories per day, while men should consume no less than 1,500 per day (unless otherwise instructed by a doctor). The generally recommended amount of calories that women should consume is around 2,000 calories per day while men should aim for 2,500 calories per day.

The following is a compilation of some common foods and their approximate calorie counts, each based on 100-gram portions from the U.S. Department of Agriculture’s (USDA) FoodData Central:

• Apple (red delicious) – 60 calories
• Broccoli – 35 calories
• Chicken breast (skinless) – 160 calories
• Grapes (red) – 81 calories
• Orange (navel) – 50 calories
• Pickles – 13 calories
• Rice (brown) – 366 calories
• Sweet potato (skinless) – 78 calories
• Tomato (Roma) – 20 calories
• Tuna (canned) – 87 calories

While calorie counting may not be for everyone, some people may find it has advantages. For one, the act of simply tracking your calorie intake can help you become more aware of your patterns and behaviors when it comes to food consumption. Becoming aware of the calories you’re eating daily is often the first step toward a behavioral change in the way you consume calories.

Certain individuals may also find power in the act of counting numbers, rather than focusing solely on the type of food they’re eating.

And arguably the biggest benefit to counting calories is possible weight loss, however, you should speak to a health professional when counting calories for weight loss as it can be difficult to sustain and is an often temporary solution.

For certain people, calorie counting may lead to some negative outcomes. First off, each person’s body is different. The amount of calories one burns can vary depending on factors including what we eat, our metabolism and the overall health of our gut.

Additionally, as a 2015 Open Heart journal article notes, a cycle of losing and regaining weight from fad diets or yo-yo dieting can be harmful to a person’s health and can lead to the development of health concerns like hypertension or insulin resistance ^[1]Malhotra A, DiNicolantonio JJ, Capewell S. It is time to stop counting calories, and time instead to promote dietary changes that substantially and rapidly reduce cardiovascular morbidity and mortality. Open Heart. 2015;2(1):e000273. Published 2015 Aug 10. . Shifting attention to food quality over quantity, explain the authors, is often a better way to reduce obesity and its related conditions

Another possible risk of counting calories is the potential for the development of an eating disorder such as anorexia, binge eating or bulimia nervosa. Recent research has also connected the use of calorie tracking apps with perpetuated behaviors or attitudes toward disordered eating.

There are a number of online trackers and calorie counting apps available to the public. Some common benefits of these apps include the ability to scan food barcodes to easily enter your foods, compatibility with other health apps or technologies and community support features.

Depending on your goals and how you want to track them, and whether you want to lose, gain or stay at your current weight, speak to your doctor or a registered dietitian to figure out the best path for you—and if a calorie counter might help.