BMR Calculator - SpeedTool

BMR Calculator

Calculate your Basal Metabolic Rate and daily calorie needs

📋 Personal Information

Your BMR (Basal Metabolic Rate)
1,768
calories/day

🔥 Daily Calorie Goals

Weight Loss
-500 cal/day
1,268
Maintenance
TDEE
1,768
Weight Gain
+300 cal/day
2,068
Formula Used
Mifflin-St Jeor Equation
Most accurate for modern adults

What is BMR?

Basal Metabolic Rate (BMR) is the number of calories your body needs to accomplish its most basic (basal) life-sustaining functions, such as breathing, circulation, and cell production. It accounts for about 60-75% of your total daily calorie expenditure.

Key Facts:

  • • BMR is highest in early adulthood (20-30 years)
  • • Males typically have 5-10% higher BMR than females
  • • Muscle mass increases BMR (more muscle = more calories burned)
  • • BMR slows down with age (about 1-2% per decade)

Mifflin-St Jeor Formula:

Male: (10 × weight_kg) + (6.25 × height_cm) − (5 × age) + 5

Female: (10 × weight_kg) + (6.25 × height_cm) − (5 × age) − 161

This formula is considered the most accurate for estimating BMR in most adults.

How to Use BMR to Lose Weight?

1. Calculate Your TDEE

Multiply your BMR by your activity multiplier to get your Total Daily Energy Expenditure. This is how many calories you burn daily including activity.

2. Create a Caloric Deficit

To lose 1 lb per week, eat 500 calories less than your TDEE. A safe deficit is 250-750 calories per day. Never go below 1,200 calories without medical supervision.

3. Combine with Exercise

Adding exercise accelerates weight loss. Cardio burns calories directly, while strength training builds muscle which increases your BMR over time.

Pro Tip: A 500 calorie daily deficit leads to approximately 1 pound (0.45 kg) of weight loss per week. This safe, gradual approach is more sustainable than extreme diets.

Activity Level Guide

Level Description Multiplier
Sedentary Desk job, little to no exercise 1.2
Lightly Active Light exercise 1-3 days/week 1.375
Moderately Active Moderate exercise 3-5 days/week 1.465
Very Active Hard exercise 6-7 days/week 1.55
Extra Active Very hard exercise, physical job 1.725