The Physics of Fuel
How MacroInspector calculates your metabolic needs using gold-standard clinical equations and modern data science.
The 3 Pillars of Your Daily Target
Calculating your daily calorie target isn't just a guess. It's a three-step mathematical process that accounts for your biology, your lifestyle, and your ultimate destination.
- checkChoose your path: Keto, High-Protein, or your own personal balance.
- checkSmart adjustments: Your targets automatically update as your weight changes.
- checkTrack it all – keep a close eye on vitamins and minerals (micronutrients) too.
BMR (Basal Metabolic Rate)
The energy your body burns just to keep your organs functioning while at rest. Think of this as your car's engine idling.
TDEE (Total Daily Energy Expenditure)
BMR multiplied by your Activity Factor. This is your "Maintenance" line—eat this much and your weight stays exactly the same.
Goal Adjustment
Applying a strategic 15% deficit for fat loss or 10% surplus for muscle gain. This "Thermodynamic Delta" is what drives change.
The Comparison Matrix
Mifflin-St Jeor
RecommendedThe modern industry gold-standard. Widely considered the most accurate formula for the general population in the 21st century.
Extremely high accuracy for sedentary to moderately active individuals. Modern research backing.
Can slightly underestimate needs for athletes with exceptionally high lean muscle mass.
Katch-McArdle
Lean Mass oriented. This formula ignores total weight and focuses entirely on your muscle mass.
The most accurate formula for athletes who know their body fat percentage.
Completely inaccurate if your body fat estimate is wrong. Requires a Smart Scale or DEXA scan.
Harris-Benedict
The clinical classic. Developed in 1919 and revised in 1984, it remains a staple in medical settings.
Decades of reliable usage and extensive peer-reviewed validation data.
Statistically tends to slightly overestimate calorie needs for modern, less active populations.
Cunningham
The choice of high-performance athletes. Similar to Katch-McArdle but with a different focus on metabolism.
Best for bodybuilders and elite athletes with extremely high LBM.
Not intended for non-athletes. Often overestimates calories for the average person.
WHO Equation
The Global Standard. A set of simple, linear equations based on extensive international demographic data.
Extremely reliable for global populations across different ages and ethnic backgrounds.
Less personalized as it doesn't account for height or specific body composition metrics.
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