Simple Calorie Intake
Calculate your daily calorie intake needs using the Mifflin-St Jeor formula for BMR and TDEE. Free online calorie calculator with energy breakdown and comparison charts.
About This Calculator
The Simple Calorie Intake Calculator estimates your daily calorie needs based on your age, gender, weight, height, and physical activity level. It uses the Mifflin-St Jeor equation — the most accurate formula for calculating Basal Metabolic Rate (BMR) — and multiplies it by an activity factor to determine your Total Daily Energy Expenditure (TDEE). This is the number of calories you need to consume each day to maintain your current weight.
BMR represents the energy your body requires at complete rest to sustain essential functions like breathing, circulation, cell production, and temperature regulation. It accounts for 60-75% of your total daily calorie burn. The remaining calories are expended through physical activity and the thermic effect of food. By estimating your TDEE accurately, you gain a solid foundation for planning your nutrition — whether your goal is weight maintenance, weight loss, or muscle gain.
Developed by researchers Mifflin and St Jeor in 1990, this equation has been validated in clinical studies as the most reliable BMR prediction method for the general population. It is updated over time and remains widely used by dietitians, nutritionists, and fitness professionals worldwide.
How to Use Your Results
For weight maintenance: Consume approximately your TDEE in calories daily.
For weight loss: Create a moderate calorie deficit of 300-500 kcal below your TDEE for safe, sustainable weight loss of 0.5-1 kg per week.
For muscle gain: Add a surplus of 200-300 kcal above your TDEE combined with resistance training.
Regional Notes
India (IN): Indian adults typically have lower average BMR values due to lower lean body mass on average. The Mifflin-St Jeor formula may slightly overestimate but remains a reliable starting point. Default values are set to metric units (kg, cm).
United States (US): This calculator uses metric units (kg, cm) for consistency. Convert your weight from pounds (1 lb = 0.454 kg) and height from inches (1 inch = 2.54 cm) before entering values. A BMI of 18.5-24.9 is considered healthy.
United Kingdom (UK): The NHS recommends the Mifflin-St Jeor formula for estimating calorie needs. UK dietary guidelines suggest a daily intake of approximately 2,500 kcal for men and 2,000 kcal for women, though individual needs vary based on the factors this calculator accounts for.
Frequently Asked Questions
What is TDEE and how is it calculated?
Total Daily Energy Expenditure (TDEE) is your total daily calorie needs. It is calculated by multiplying your Basal Metabolic Rate (BMR) by an activity factor that reflects your exercise level. This calculator uses the Mifflin-St Jeor equation, the most accurate formula for estimating BMR.
What is BMR and why is it important?
Basal Metabolic Rate (BMR) is the minimum number of calories your body needs at complete rest to maintain vital functions like breathing, circulation, and cell production. It accounts for approximately 60-75% of your total daily calorie expenditure and varies based on age, gender, weight, and height.
Is this calculator free to use?
Yes, it is completely free to use with no registration or hidden charges. You can also share your results via URL for easy bookmarking.
How accurate is the Mifflin-St Jeor formula?
The Mifflin-St Jeor equation is considered the most accurate BMR formula for the general population, with an accuracy of about 85-90% in healthy individuals. It was developed in 1990 and validated in multiple studies as more precise than the older Harris-Benedict equation.
How do I choose the right activity level?
Choose Sedentary if you sit most of the day with little exercise. Light if you exercise 1-3 days weekly. Moderate if you exercise 3-5 days weekly. Active if you exercise 6-7 days weekly. Very Active if you have physically demanding work plus daily exercise or train twice daily.
Can this calculator help with weight loss planning?
Yes, once you know your TDEE (maintenance calories), you can create a calorie deficit for weight loss by consuming 300-500 fewer calories per day, which typically leads to 0.5-1 kg of weight loss per week. Always consult a healthcare professional before starting any diet.
Does the calculator work for all body types?
The Mifflin-St Jeor formula works well for most adults. However, individuals with very high muscle mass may have a higher BMR, while those with higher body fat may have a slightly lower BMR than calculated. For personalized advice, consult a registered dietitian.