BMR Calculator

Calculate your Basal Metabolic Rate (BMR) to discover how many calories your body burns at rest to sustain vital bodily functions.

Calculator Inputs

Biological sex impacts lean mass ratio.
yrs
Metabolism naturally declines with age.
in
Total height.
lbs
Current weight.

Calculated Results

Basal Metabolic Rate (BMR)
1,747 kcal / day
Hourly Calorie Burn at Rest 72.8 kcal/hr
Sedentary TDEE (x1.2) 2,096 kcal
Moderate TDEE (x1.55) 2,708 kcal
Values calculate live as you adjust inputs.

About BMR Calculator

What is the BMR Calculator?

The BMR Calculator is an enterprise-grade calculation tool designed to compute exact mathematical, financial, or scientific parameters based on peer-reviewed formulas.

How to Use This Calculator

  1. Enter your primary input variables in the input fields above.
  2. Select your desired measurement units or options.
  3. Click Calculate to instantly view live outputs, step-by-step mathematical breakdowns, and formulas.

Mathematical Formula & Derivation

Our calculation engine implements verified equations approved by academic literature, WHO guidelines, IRS tax codes, or BIPM metric standards.

Frequently Asked Questions

Q: Is this calculator free to use?
A: Yes! OmniCalc Ultra provides 100% free, private, client-side calculations with zero tracking.

Scientific & Academic References

  • International System of Units (SI) Standards
  • NIST Engineering & Mathematical Reference Handbooks

What is BMR Calculator?

Basal Metabolic Rate (BMR) is the baseline number of calories required to keep your body functioning at complete physical and mental rest in a temperate environment.

How to Use This Calculator

  1. Enter biological sex, age, total height, and body weight.
  2. The calculator applies the clinical Mifflin-St Jeor formula.
  3. Review your resting energy expenditure before factoring in daily movement or exercise.

The Mathematical Formula & Variables

Men: BMR = (10 * weight in kg) + (6.25 * height in cm) - (5 * age) + 5; Women: BMR = (10 * weight in kg) + (6.25 * height in cm) - (5 * age) - 161

Variables Definition

Symbol / Variable Name Description
W Weight Mass in kilograms.
H Height Stature in centimeters.
A Age Chronological age in completed years.

Step-by-Step Worked Example

Scenario: 30-year-old female, 5 ft 5 in (165 cm), 140 lbs (63.5 kg).

  1. Weight contribution: 10 * 63.5 = 635.
  2. Height contribution: 6.25 * 165 = 1,031.25.
  3. Age deduction: 5 * 30 = 150.
  4. Female sex offset: -161.
  5. BMR = 635 + 1,031.25 - 150 - 161 = 1,355.25 kcal/day.

Result: BMR = 1,355 Calories/day at complete rest.

Frequently Asked Questions

Should I eat below my BMR to lose weight faster?

Eating below your BMR is generally not recommended because your body needs those calories to power vital cellular and organ functions. Prolonged severe deficits trigger metabolic adaptation and loss of lean muscle.