BridgeAthletic has two nutrition calculators:
TDEE Calculator – Estimates daily calories burned
Gram-Per-Kilogram Calculator – Sets macros based on body weight
TDEE Calculator
TDEE = Total Daily Energy Expenditure (calories burned in 24 hours)
The Formula
TDEE = BMR × Activity Factor
Step 1: Calculate BMR
BMR = Basal Metabolic Rate (calories burned at rest)
The calculator uses one of two formulas:
Without Body Fat % – Mifflin-St Jeor
Male/Not Listed: (10 × weight kg) + (6.25 × height cm) – (5 × age) + 5
Female: (10 × weight kg) + (6.25 × height cm) – (5 × age) – 161
With Body Fat % – Katch-McArdle
BMR = 370 + (21.6 × Lean Body Mass kg)
Lean Body Mass = Weight kg × (1 – Body Fat %)
Step 2: Multiply by Activity Level
Activity Level | Multiplier |
Sedentary (desk job, little exercise) | 1.2 |
Lightly Active (exercise 1–3 days/week) | 1.375 |
Moderately Active (exercise 6–7 days/week) | 1.55 |
Very Active (hard exercise daily) | 1.725 |
Extra Active (hard exercise 2×/day) | 1.9 |
Step 3: Adjust for Goals
Use the slider to adjust –20% (weight loss) to +20% (weight gain).
Gram-Per-Kilogram Calculator
Sets macro targets based on body weight.
The 3 Steps
1. Convert to kilograms
Weight lbs ÷ 2.205 = Weight kg
2. Calculate grams
Weight kg × g/kg target = grams of each macro
3. Convert to calories
Macro | Calories per gram |
Protein | 4 |
Carbs | 4 |
Fat | 9 |
Example: 210 lb Male, Age 20, 6'0", Moderately Active
TDEE Calculation
BMR (Mifflin-St Jeor):
Weight: 210 lbs ÷ 2.205 = 95.24 kg
Height: 6'0" = 182.88 cm
BMR = (10 × 95.24) + (6.25 × 182.88) – (5 × 20) + 5 = 2,000 kcal
TDEE:
2,000 × 1.55 = 3,100 kcal
Macro Calculation
Settings: Protein 2.1 g/kg | Carbs 5 g/kg | Fat 1 g/kg
Macro | Grams | Calories | % |
Protein | 95.24 × 2.1 = 200 g | 800 | 22% |
Carbs | 95.24 × 5.0 = 476 g | 1,905 | 53% |
Fat | 95.24 × 1.0 = 95 g | 857 | 24% |
TOTAL |
| 3,562 | 100% |
Recommended Ranges
Setting | Range | Typical |
Protein | 0.8–2.2 g/kg | 0.8–2.2 g/kg |
Carbs | 2–12 g/kg | 3–7 g/kg |
Fat | 0.5–3 g/kg | 0.8–1.5 g/kg |
Calorie Adjustment | –500 to +500 kcal | 0 |
Quick Reference
BMR:
Male/Not Listed = (10 × wt kg) + (6.25 × ht cm) – (5 × age) + 5
Female = (10 × wt kg) + (6.25 × ht cm) – (5 × age) – 161
Katch-McArdle = 370 + (21.6 × LBM kg)
TDEE & Macros:
TDEE = BMR × Activity Factor
Macro grams = weight kg × g/kg target
Calories = (Protein g × 4) + (Carbs g × 4) + (Fat g × 9)