Carb Cycling Calculator
Calculate your high, medium, and low carb day macros for a carb cycling nutrition plan.
Results
Visualization
How It Works
Carb cycling alternates between high-carb and low-carb days throughout the week, typically aligning high-carb days with intense training sessions and low-carb days with rest. This approach aims to fuel performance when needed while promoting fat oxidation on rest days.
The Formula
Variables
- TDEE — Total Daily Energy Expenditure at maintenance
- Protein — Kept constant at ~1 g/lb body weight across all day types
- High_Day — Training day calories set at 110% of TDEE with emphasis on carbs
- Low_Day — Rest day calories set at 85% of TDEE with emphasis on fats
- Weekly_Avg — Average daily calories across the full week
Worked Example
A 70 kg person with a 2,200 kcal TDEE training 4 days/week: Protein = 154 g (all days). High day (2,420 kcal): 154 g protein, 237 g carbs, 51 g fat. Low day (1,870 kcal): 154 g protein, 78 g carbs, 81 g fat. Weekly average = (2,420*4 + 1,870*3) / 7 = 2,184 kcal.
Practical Tips
- Schedule high-carb days on your hardest training sessions (legs, full-body) for maximum performance benefit.
- Keep protein constant every day - only cycle carbs and fats to simplify the approach.
- Time most of your carbs around your workout (before and after) on high days for optimal glycogen replenishment.
- Low-carb days are not zero-carb; keep at least 50-75 g for brain function and mood stability.
- Give carb cycling at least 4-6 weeks before judging results, as your body needs time to adapt to the cycling pattern.
Frequently Asked Questions
Is carb cycling better than a straight diet?
For most people, total calorie balance matters more than carb timing. However, carb cycling can improve training performance on hard days, enhance dietary adherence by allowing higher-calorie days, and may have modest benefits for body composition.
What should I eat on high-carb days?
Focus on complex carbohydrates like oats, rice, potatoes, sweet potatoes, fruits, and whole grain bread. These provide sustained energy and glycogen replenishment. Save simpler carbs for immediately post-workout.
Can I do carb cycling while building muscle?
Yes. Set your weekly average above maintenance by 200-300 kcal. High-carb training days provide the anabolic environment and fuel for heavy lifting, while moderate days still support recovery.
How do I handle medium-carb days?
Medium days work well for light training, active recovery, or cardio sessions. They sit between your high and low targets and help smooth out the weekly calorie average. Not everyone needs them; a simple high/low split works too.
Will low-carb days make me feel tired?
There may be an adjustment period of 1-2 weeks. Schedule low-carb days on rest days to minimize impact. Ensuring adequate fat intake on these days provides alternative fuel and helps maintain energy and satiety.