Calorie & TDEE Calculator

1. Select your preferred unit system (Metric or Imperial).
2. Choose your gender by clicking Male or Female.
3. Enter your age, weight, and height.
4. Select your activity level from the dropdown.
5. Your BMR, TDEE, and calorie goals for losing, maintaining, or gaining weight are displayed instantly.

What is a Calorie Calculator?

A calorie calculator estimates how many calories your body needs each day based on your age, gender, weight, height, and activity level. It works by first calculating your Basal Metabolic Rate (BMR), the number of calories your body burns at complete rest to sustain vital functions like breathing and circulation, and then multiplying that figure by an activity factor to arrive at your Total Daily Energy Expenditure (TDEE). Knowing your TDEE allows you to set calorie targets for weight loss, maintenance, or weight gain. This tool uses the Mifflin-St Jeor equation, which was published in 1990 and is widely regarded as the most accurate general-purpose BMR formula available today.

How the Mifflin-St Jeor Formula Works

The Mifflin-St Jeor equation calculates BMR using your weight in kilograms, height in centimeters, and age in years. The formula for men is: BMR = (10 x weight) + (6.25 x height) - (5 x age) + 5. For women, the formula is: BMR = (10 x weight) + (6.25 x height) - (5 x age) - 161. Once your BMR is determined, it is multiplied by an activity factor ranging from 1.2 (sedentary) to 1.9 (extra active) to estimate your TDEE. The result represents the total number of calories you burn in a typical day. To lose weight, subtract 500 calories per day from your TDEE for roughly one pound of fat loss per week. To gain weight, add 500 calories per day. These are standard guidelines, but individual results will vary.

Common Use Cases

• Setting a daily calorie budget for sustainable weight loss
• Determining calorie needs for lean muscle gain (bulking)
• Establishing a maintenance intake to stabilize your current weight
• Planning meal prep and nutrition programs around a specific calorie target
• Comparing calorie needs at different activity levels to understand the impact of exercise
• Pairing with macro tracking for optimized body composition results

Tips for Accurate Calorie Tracking

Most people overestimate their activity level and underestimate their food intake. When selecting an activity level, be conservative. A desk job with three gym sessions per week is "lightly active" at best, not "moderately active." The activity multipliers range from 1.2 to 1.9, and choosing the wrong tier can swing your estimated TDEE by 500 or more calories. Start with a lower activity level and adjust based on real-world results over two to three weeks.

When tracking food, use a kitchen scale rather than eyeballing portions. Track consistently for two to four weeks to build awareness of portion sizes and calorie density, then transition to intuitive eating if you prefer. Weigh yourself at the same time each morning and look at the weekly average rather than daily fluctuations, which are influenced by water retention, sodium intake, and meal timing. A 500-calorie daily deficit produces roughly one pound of fat loss per week. If the scale is not moving after two weeks of consistent tracking, you are likely consuming more than you realize. The Mifflin-St Jeor equation is accurate within about 10% for most people, but individual factors such as genetics, hormones, and body composition can shift your actual metabolic rate. Always consult a healthcare professional before beginning a very low-calorie diet (below 1,200 calories for women or 1,500 for men).

Related Health Tools

Once you know your calorie needs, break them into protein, carbs, and fat targets with our Macro Calculator. For a deeper look at energy expenditure across every activity level, try the TDEE Calculator. You can also check your weight classification with the BMI Calculator or estimate your composition with the Body Fat Calculator.