Lean Bulk Calculator
Find the calories and protein you need to build muscle without piling on fat. The calculator works out your maintenance (TDEE) and adds a controlled surplus — +250 for a lean bulk, +500 for a standard bulk — plus your daily protein target.
Lean bulk (+250)
2,943
cal/day · ~0.5 lb/week
Standard bulk (+500)
3,193
cal/day · ~1 lb/week
Daily protein target
123–170 g
0.7–1 g per lb bodyweight
Maintenance (TDEE) 2,693 cal/day · Mifflin-St Jeor · activity ×1.55
Calorie targets by goal
| Goal | Calories/day |
|---|---|
| Weight loss (−1 lb/week) | 2,193 |
| Mild weight loss (−0.5 lb/week) | 2,443 |
| Maintain weight | 2,693 |
| Mild weight gain (+0.5 lb/week) | 2,943 |
| Weight gain (+1 lb/week) | 3,193 |
TDEE at every activity level
| Activity level | Multiplier | Calories/day |
|---|---|---|
| Sedentary (little or no exercise) | ×1.2 | 2,085 |
| Light (exercise 1–3 days/week) | ×1.375 | 2,389 |
| Moderate (exercise 3–5 days/week) | ×1.55 | 2,693 |
| Very active (hard exercise 6–7 days/week) | ×1.725 | 2,997 |
| Extra active (physical job + training) | ×1.9 | 3,301 |
Why a small surplus wins
Muscle growth has a speed limit set by training experience and recovery — roughly 1–2 pounds per month for beginners and half that for intermediates. Calories beyond what that growth requires are stored as fat, which is why a +250 surplus builds nearly as much muscle as +500 while gaining visibly less fat. The price is patience: a lean bulk phase typically runs 4–6 months before a short cut.
Pair the calories with 0.7–1 g of protein per pound of bodyweight, progressive overload in training, and 7–9 hours of sleep. Use the macro calculator to split your surplus into protein, carbs and fat, the body fat calculator to decide whether to bulk or cut first, and the TDEE calculator for the full activity-level breakdown.