OmniTools

TDEE & Macro Nutrition Calculator (BMR)

Calculate total daily energy expenditure (TDEE), BMR, and optimal Carbs/Protein/Fat macro splits for diet goals.

Basis: The Mifflin-St Jeor (1990) equation, with the conventional five Harris-Benedict style activity multipliers (1.2–1.9)·2026-08-28 verified·Not reviewed by a medical professional·Editorial policy

Before you rely on this

An estimate, not a measurement. At the same height, weight and age, real resting metabolic rate varies by roughly ±10–20% with body composition and thyroid function. The activity multiplier is self-selected and easy to overestimate, which inflates total daily energy expenditure.

Tool Overview & Key Purpose

Calculate Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) to design macro diets for fat loss, maintenance, or muscle gain.

Step-by-Step Usage Instructions

1STEP 1

Enter gender, age, height, and current weight.

2STEP 2

Select activity multiplier level (Sedentary, Lightly Active, Moderately Active, Very Active).

3STEP 3

View calculated BMR and TDEE (Total Daily Energy Expenditure).

4STEP 4

Select personal goal (-1 lb/week fat loss, maintenance, or lean gain) to get exact target calories.

Real-World Scenarios & Practical Cases

3 Practical CasesScenario #1

Fat Loss Plan for Moderately Active Male

BMR 1,680 kcal, TDEE 2,350 kcal. Consuming 1,850 kcal daily (-500 kcal deficit) results in ~1 lb fat loss per week.

A 500 kcal daily deficit equals roughly 3,500 kcal or 1 lb fat loss weekly.Scenario #2

Lean Muscle Bulking Strategy

For TDEE 2,100 kcal, eating 2,350 kcal (+250 kcal surplus) supports muscle hypertrophy without excess fat storage.

Combine small caloric surplus with high protein intake.Scenario #3

Overcoming Weight Loss Plateau

Recalculating TDEE after dropping 15 lbs adjusts caloric intake to match your lower baseline weight.

Recalculate TDEE after every 5-10 lbs lost.BMR estimation formulaMifflin-St Jeor: BMR = (10×wt) + (6.25×ht) - (5×age) + s ; TDEE = BMR × Activity Multiplier

Pro Tips & Key Considerations

Never consume fewer calories than your BMR for extended periods to protect metabolic rate.Aim for 1.6 - 2.2g of protein per kg of body weight during calorie deficits.

Frequently Asked Questions (FAQ)

Sources & References

Mifflin et al., "A New Predictive Equation for Resting Energy Expenditure" (Am J Clin Nutr, 1990)CDC — About Healthy Weight and Growth

Basis: The Mifflin-St Jeor (1990) equation, with the conventional five Harris-Benedict style activity multipliers (1.2–1.9) · 2026-08-28 verified