Calorie Calculator

Calorie Calculator

Estimate your daily calorie needs for your goals.

Introduction

Welcome to the Calorie Calculator! This tool estimates your daily calorie needs based on your age, gender, height, weight, and activity level using the Mifflin-St Jeor Equation. Whether you want to maintain your weight, lose weight, or gain weight, this calculator provides personalized calorie targets to help you achieve your goals.

How to Use

  1. Select your unit system: Metric (kg, cm) or Imperial (lbs, inches).
  2. Enter your gender, age, weight, height, and activity level.
  3. Click "Calculate" to see your daily calorie needs for maintenance, weight loss, and weight gain.
  4. Click "Save Calculation" to store your results locally.
  5. Use "Reset" to clear all inputs and start over.

Understanding Calorie Needs

What is BMR and TDEE?

Your Basal Metabolic Rate (BMR) is the number of calories your body needs at rest to maintain basic functions like breathing and circulation. Total Daily Energy Expenditure (TDEE) is your BMR multiplied by an activity factor, representing the total calories you burn daily.

How We Calculate

We use the Mifflin-St Jeor Equation to calculate BMR:
For men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) + 5
For women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) − 161
TDEE = BMR × Activity Factor
Weight loss/gain targets are adjusted by 500 calories/day (approximately 0.5 kg/week).

Using Your Results

Maintenance: Eat your TDEE calories to maintain your weight.
Weight Loss: Eat 500 calories less than your TDEE to lose about 0.5 kg (1 lb) per week.
Weight Gain: Eat 500 calories more than your TDEE to gain about 0.5 kg (1 lb) per week.

Limitations

This calculator provides an estimate. Individual calorie needs may vary due to metabolism, muscle mass, and other factors. Consult a dietitian for a personalized plan.

FAQs

How accurate is this calculator?

The Mifflin-St Jeor Equation is one of the most accurate for estimating calorie needs, but it’s still an estimate. Your actual needs may vary.

Can I use this calculator if I’m pregnant?

Pregnant women have higher calorie needs. Consult your healthcare provider for guidance during pregnancy.

What if I have a medical condition?

Medical conditions like thyroid issues can affect your metabolism. Speak with a doctor or dietitian for tailored advice.

About This Calculator

Built by xAI, this Calorie Calculator uses the Mifflin-St Jeor Equation to estimate your daily calorie needs. For a personalized nutrition plan, consult a dietitian or healthcare provider.