Back to all tools

Carb Cycling Calculator

Plan high, moderate, and low carb days around your training split to build muscle and lose fat without sacrificing performance.

What carb cycling is and who it suits

Carb cycling is a meal planning strategy that varies daily carbohydrate intake based on training demand while keeping protein roughly constant and adjusting fat to balance total energy. The typical pattern uses high-carb days on intense training sessions, moderate-carb days on lighter training days and low-carb days on rest days. A common template for a 75-kilogram lifter in a small deficit might look like 4 to 5 grams of carbohydrate per kilogram on high days, 2 to 3 grams per kilogram on moderate days and 0.5 to 1 gram per kilogram on rest days. Protein stays at 2 to 2.2 grams per kilogram throughout, and fat fills the gap to hit the weekly calorie target. The goal is to position carbohydrate where it supports performance and recovery while creating larger deficits on days when glucose demand is low. Evidence base consists of mechanistic plausibility and field experience from bodybuilding, with limited large randomized trial support.

Practical carb cycling templates by goal

For muscle gain, use a small calorie surplus across the whole week with three to five high-carb days positioned on heavy training days. Total carbohydrate over the week averages around 4 to 5 grams per kilogram daily. For fat loss with training performance preservation, use a moderate weekly deficit of roughly 20 percent from maintenance, with two high-carb days on the most intense sessions to protect training quality, three moderate-carb days and two low-carb days stacked on rest. For body recomposition at maintenance, match weekly energy to maintenance and skew carbohydrate toward training days without a net deficit or surplus. Regardless of the goal, protein should remain steady and high, hydration should stay constant, and micronutrient intake from fruits and vegetables should be consistent daily. Low days do not mean keto, simply reduced carbohydrate relative to your personal average.

Frequently Asked Questions

Is carb cycling more effective than a steady diet?▼
Evidence is limited and mixed. No large randomized trial demonstrates clear superiority of carb cycling over isocaloric steady diets for fat loss or muscle gain when protein is matched. The mechanism is biologically plausible but effect sizes appear small. The main practical benefit is adherence for people who feel better with structured variation in carbohydrate intake, especially those coming off aggressive low-carb approaches. For most people a steady diet with carbohydrate skewed toward training meals captures 90 percent of any benefit.
How do I set my protein target for carb cycling?▼
Keep protein constant across all days at 1.8 to 2.4 grams per kilogram of body weight, with 2.0 to 2.2 grams per kilogram being a safe default for most lifters. In a cutting phase favor the upper end at 2.2 to 2.4 grams per kilogram to protect lean mass. Distribute protein across three to five meals, aiming for 0.3 to 0.4 grams per kilogram per meal. Varying protein while varying carbohydrate creates confounds and makes troubleshooting hard.
Can I do carb cycling on a plant-based diet?▼
Yes, but it requires more planning. Plant protein sources often come with substantial carbohydrate, so hitting a true low-carb day means leaning heavily on tofu, tempeh, seitan, soy protein powder and lower-carb vegetables like leafy greens, broccoli and cauliflower. High-carb days can use rice, oats, legumes and fruit. Micronutrient coverage matters more than usual on low days, so watch iron, zinc, iodine, B12 and omega-3 intake via supplementation where appropriate.
Macro CalculatorCarb Intake CalculatorTDEE Calculator

Explore our other free fitness calculators: View all tools