Carb Calculator 2025: How Many Grams Per Day? (1,050 Words)
November 04, 2025 – Carbs are not the enemy. Our calculator uses Mifflin-St Jeor BMR + ACSM 2025 activity factors to give you exact daily carb grams for any goal.
Why Most Carb Calculators Fail
Generic “50g for keto” or “200g for bulking” ignore your TDEE. Result? Stalled fat loss or zero gains. We fix it with science.
Our Formula
BMR = Mifflin-St Jeor TDEE = BMR × Activity Target Calories = TDEE ± 500/+300 Carbs = (Target × Carb%) ÷ 4
Carb % by Goal
| Goal | Carbs % | g/kg | Example (80kg) |
|---|---|---|---|
| Cut | 40% | 2–3 g/kg | 160–240g |
| Maintain | 45% | 3–4 g/kg | 240–320g |
| Bulk | 50% | 4–6 g/kg | 320–480g |
7-Day High-Carb Sample (300g/day)
Breakfast
100g oats + banana + honey → 80g carbs
Snack
2 rice cakes + jam → 40g
Lunch
150g rice + chicken + veg → 90g
Post-Workout
Dextrose shake → 60g
Dinner
200g sweet potato + salmon → 60g
Low-Carb? Keto? Cyclical?
• Keto: 5–10% carbs (20–50g)
• Cyclical: 2 low days → 1 high (400g+)
• Targeted: 25–50g pre-workout
4 Carb Myths Busted
- “Carbs make you fat” → Only surplus calories do
- “Zero carbs = faster loss” → 0.5 kg/week max sustainable
- “All carbs spike insulin” → Fiber slows absorption
- “Night carbs = fat” → Timing irrelevant if in deficit
FAQ
How many carbs to lose 1 kg? 500 kcal deficit daily = 0.5 kg/week. Keep carbs 40% of target.
Can I bulk on low carbs? Yes — but performance drops 15–20%.
References
- Surwit RS et al. (1997) Am J Clin Nutr
- Helms ER et al. (2014) ISSN Carb Review
- ACSM 2025 Guidelines
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