Calorie Calculator
Calculate daily calorie needs (TDEE) from age, weight, height, and activity.
Written by Golam Rabbani, Founder & Lead Engineer — Last updated 2026-05-01
How to use this calorie calculator
- Enter your age in years and select your gender.
- Toggle between kg and lbs, then enter your weight.
- Toggle between cm and ft, then enter your height.
- Select your activity level from the dropdown.
- Press Calculate to see your BMR, TDEE, and goal-based calorie targets.
About this calorie calculator
The calorie calculator works out how many calories your body needs each day based on your age, gender, weight, height, and activity level. It returns two core numbers — your Basal Metabolic Rate (BMR) and your Total Daily Energy Expenditure (TDEE) — plus a table of daily calorie targets for weight loss, mild weight loss, maintenance, and weight gain.
The tool uses the Mifflin-St Jeor equation, which is widely regarded as the most accurate general-purpose BMR formula. For males the formula is: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5. For females, the constant at the end is −161 instead of +5. TDEE is then calculated by multiplying BMR by an activity factor ranging from 1.2 (sedentary) to 1.9 (very active hard daily exercise). The weight-loss and weight-gain targets apply a standard ±500 kcal/day offset from TDEE, while mild weight loss uses −250 kcal/day. This is an estimate for general information and is not a substitute for advice from a qualified clinician.
For example, a 30-year-old male who weighs 80 kg and is 180 cm tall with a moderate activity level (factor 1.55) has a BMR of approximately 1,858 kcal/day and a TDEE of roughly 2,880 kcal/day, giving a weight-loss target of about 2,380 kcal/day. The tool is useful for anyone tracking nutrition, planning a calorie deficit, or setting a maintenance target. This calculator is for general educational purposes only and is not medical advice — consult a licensed healthcare professional for personal guidance.
FAQ
- What does a calorie calculator measure?
- A calorie calculator estimates the number of kilocalories (kcal) your body burns per day, both at rest (BMR) and accounting for physical activity (TDEE). The result is used as a baseline for setting daily calorie targets.
- What formula does the calorie calculator use?
- It uses the Mifflin-St Jeor equation: BMR = (10 × kg) + (6.25 × cm) − (5 × age) + 5 for males, or − 161 for females. TDEE is BMR multiplied by an activity factor between 1.2 and 1.9.
- How accurate are the calorie estimates?
- The Mifflin-St Jeor formula is considered the most accurate standard BMR equation for most adults, but individual metabolism varies. Treat the output as a practical starting point and adjust based on real-world results over several weeks.
- What happens if I enter an age outside the valid range?
- The tool only accepts ages between 1 and 120. If you enter a value outside that range or leave the field empty, it shows an error message and will not calculate until you correct the input.
- Does this tool store my personal data?
- No. The calorie calculator runs entirely in your browser. Your age, weight, height, and other inputs are never sent to a server or saved between visits — closing the tab clears everything.
- Is the calorie calculator free?
- Yes. It is completely free to use with no signup, no account, and no usage limits.