“How many calories should I eat?” is one of the most common nutrition questions, and it starts with a straightforward formula: estimate your resting metabolic rate, then scale it by how active you actually are.
What Is the Calorie Calculator?
Enter your sex, age, height, weight, and activity level, and the tool instantly calculates your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation, your Total Daily Energy Expenditure (TDEE) after applying an activity multiplier, and a suggested weight-loss calorie target using a common 500-calorie/day deficit.
How to Use It
- Open the tool at /tools/calorie-calculator.
- Select your sex and enter your age, height (cm), and weight (kg).
- Choose the activity level that best matches your typical week.
- Read your BMR, TDEE, and weight-loss target, updated live as you adjust any field.
Key Features
- Mifflin-St Jeor equation, widely considered more accurate for modern populations than the older Harris-Benedict formula.
- Five activity levels, from sedentary to very active, each with its own scientifically-referenced multiplier.
- Live updates as you change any input, with no submit button needed.
- Fully client-side — your health data never leaves your browser.
When to Use This Tool
- Planning a weight-loss, maintenance, or muscle-gain calorie target.
- Understanding the difference between BMR and TDEE before starting a nutrition plan.
- Quick estimates for fitness tracking apps that ask you to set a daily calorie goal.
Try It Now
Open Calorie Calculator directly, or press ⌘K and type the tool name from anywhere on the site.
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