Calculator
Formula Used
Mifflin-St Jeor: male BMR = 10W + 6.25H - 5A + 5. female BMR = 10W + 6.25H - 5A - 161.
Katch-McArdle: BMR = 370 + 21.6 × lean body mass in kilograms.
Revised Harris-Benedict: uses weight, height, age, and sex constants.
Maintenance: TDEE = BMR × activity multiplier.
Muscle gain target: Target calories = TDEE + selected surplus.
Macros: protein calories = protein grams × 4. fat calories = fat grams × 9. carbs = remaining calories ÷ 4.
Weekly gain estimate: estimated kilograms = weekly surplus ÷ 7700.
How to Use This Calculator
- Select your unit system.
- Enter age, sex, height, weight, and body fat.
- Choose the BMR formula that fits your data.
- Select your activity level and training days.
- Choose a surplus style or enter a custom surplus.
- Set protein and fat preferences.
- Press the calculate button.
- Download the result as CSV or PDF.
Example Data Table
| Person | Weight | Height | Activity | Surplus | Protein | Fat | Meals |
|---|---|---|---|---|---|---|---|
| Beginner lifter | 70 kg | 175 cm | Moderate | Lean | 2.0 g/kg | 0.8 g/kg | 4 |
| Hard gainer | 82 kg | 183 cm | Very active | Aggressive | 2.2 g/kg | 25% | 5 |
| Controlled bulk | 165 lb | 70 in | Light | Custom 250 | 1.9 g/kg | 0.7 g/kg | 3 |
Muscle Gain Macro Guide
Smart Muscle Gain Planning
A muscle gain plan works best when food supports training. Calories create the growth environment. Protein supplies amino acids for repair. Carbohydrates refill muscle glycogen. Fats support hormones and steady energy. This calculator joins those parts in one simple workflow.
Calorie Surplus and Control
Muscle gain usually needs a surplus. A surplus means you eat more than your daily burn. The tool estimates maintenance calories first. It then adds a selected surplus. Lean gaining uses a smaller surplus. Aggressive gaining uses a larger one. A moderate plan often gives a good balance. It supports growth while limiting excess fat gain.
Protein, Carbs, and Fats
Protein is based on body weight. Many lifters use a higher setting during hard training. Fats can be set by body weight or calorie share. Carbs receive the remaining calories after protein and fats. This method keeps the plan balanced. It also prevents random macro targets. Carbohydrates are useful near workouts. They can improve training output and recovery.
Training Day Adjustments
The calculator can also split calories by day type. Training days may receive more calories. Rest days may receive fewer calories. The weekly average still matches the chosen target. This is helpful for people who train several days each week. It can place more food when performance matters most.
Using Results Wisely
Results are estimates, not fixed rules. Track body weight, gym performance, appetite, and energy. Review weekly averages, not single days. If weight rises too fast, reduce calories slightly. If strength stalls and weight is flat, add a small amount. Keep protein steady. Adjust carbs or fats first. Stay consistent for at least two weeks before major changes.
Healthy Progress
Good muscle gain is patient. Sleep, progressive overload, hydration, and meal timing all matter. A calculator cannot replace coaching or medical advice. It can give structure. It can make changes easier to measure. Use it as a planning guide, then refine it with real progress data.
Advanced Input Choices
Body fat entry improves lean mass estimates. Activity multipliers reflect lifestyle and job movement. Meal count breaks totals into daily servings. Export buttons help save records. Compare entries over time to see which surplus supports muscle without unwanted weight gain safely.
FAQs
What is a macro calculator for muscle gain?
It estimates daily calories, protein, carbs, and fats for gaining muscle. It uses body details, activity, training days, and a calorie surplus to create practical targets.
Which BMR formula should I use?
Use Mifflin-St Jeor for most people. Use Katch-McArdle when you know body fat. Use Harris-Benedict if you prefer that older, common method.
How much surplus is best for lean muscle gain?
A smaller surplus often works well. Five to ten percent above maintenance is common. It supports progress while reducing unnecessary fat gain.
Can I use this calculator during a bulk?
Yes. Choose moderate or aggressive surplus based on your training age, appetite, and weight trend. Review progress every one or two weeks.
Why are carbs calculated last?
Protein and fats are usually set first. Carbs use the remaining calories. This gives energy for training while keeping essential macro targets covered.
Should training days have more calories?
Some lifters prefer that. Extra training day calories can improve workout fuel. The calculator balances rest days against the weekly average.
Is the weekly gain estimate exact?
No. It is only a rough estimate. Water, digestion, training stress, and tracking errors can change scale weight from week to week.
Do I need medical advice before using it?
Ask a qualified professional if you have a medical condition, eating disorder history, or special nutrition needs. This tool is only a planning aid.