Refeed Day Calculator
Calculate refeed day calories and macros for metabolic recovery during fat loss phases. Enter values for instant results with step-by-step formulas.
Calculator
Adjust values & calculateCurrent Cutting Macros
Weekly Impact
Formula
Refeed calories are set at approximately 105% of estimated TDEE to provide a slight surplus. Protein remains constant from the cutting phase. Fat is reduced to 70% of cutting levels to make room for more carbs. All extra calories come from carbohydrates to maximize leptin restoration and glycogen replenishment.
Last reviewed: January 2026
Worked Examples
Example 1: Lean Male Refeed Day Setup
Example 2: Female Competitor Refeed
Background & Theory
The Refeed Day Calculator applies the following established principles and formulas. Health and medicine calculators are grounded in validated physiological measurement methods established through decades of clinical research. Body Mass Index, or BMI, is calculated by dividing weight in kilograms by height in meters squared (kg/m²), a formula originating from Adolphe Quetelet's 19th-century statistical work and later codified by the WHO into standard classifications: underweight below 18.5, normal weight 18.5 to 24.9, overweight 25 to 29.9, and obese at 30 and above. Basal Metabolic Rate quantifies the minimum energy required to sustain life at rest. The Mifflin-St Jeor equation, published in 1990 and widely regarded as the most accurate for most adults, calculates BMR as (10 × weight in kg) + (6.25 × height in cm) − (5 × age) ± sex adjustment. The older Harris-Benedict equations, revised in 1984 by Roza and Shizgal, remain in common use. Total Daily Energy Expenditure is derived by multiplying BMR by a physical activity factor ranging from 1.2 for sedentary individuals to 1.9 for extremely active ones, following the methodology validated by doubly labeled water studies. Body fat percentage can be estimated without laboratory equipment using the U.S. Navy circumference method, which uses neck, waist, and hip measurements, or via BMI-derived equations adjusted for age and sex. The Jackson-Pollock skinfold method offers higher precision with calipers. Blood pressure classification, according to the American College of Cardiology and the 2017 ACC/AHA guidelines, defines normal as below 120/80 mmHg, elevated as 120 to 129 systolic, and hypertension stage 1 as 130 to 139 systolic or 80 to 89 diastolic. Target heart rate zones for aerobic exercise are derived from maximum heart rate estimates, most commonly using the formula 220 minus age in years, with moderate-intensity training typically defined as 50 to 70 percent of maximum heart rate and vigorous intensity at 70 to 85 percent, consistent with CDC and American Heart Association guidelines. These thresholds guide safe and effective cardiovascular conditioning.
History
The history behind the Refeed Day Calculator traces back through the following developments. The history of health measurement stretches back to ancient Greece, where Hippocrates around 400 BCE laid the foundation for observational medicine by systematically recording patient symptoms, diet, and environment. His humoral theory, though scientifically superseded, established the principle that the body operates as an interconnected system subject to measurable imbalance. The transformation toward modern medicine accelerated in the 19th century. Louis Pasteur and Robert Koch developed germ theory in the 1860s and 1870s, identifying microorganisms as disease agents and enabling targeted interventions. Florence Nightingale, working during the Crimean War in the 1850s, introduced statistical analysis to nursing practice, demonstrating through data visualization that sanitation reduced mortality. Her work is foundational to evidence-based health measurement. The discovery of vitamins in the early 20th century, beginning with Casimir Funk's coinage of the term in 1912 and culminating in the isolation of vitamins A through K, created the field of nutritional science and gave rise to dietary reference intake frameworks. The World Health Organization, founded in 1948, subsequently established global standards for health metrics, disease classification through the International Classification of Diseases, and recommended daily allowances. The BMI as a clinical screening tool gained traction in the 1970s through Ancel Keys' large-scale epidemiological work, which validated Quetelet's index as a population-level obesity indicator. Through the 1980s and 1990s, the Framingham Heart Study produced landmark data linking cholesterol, blood pressure, and lifestyle factors to cardiovascular disease risk, directly shaping the numeric thresholds still used in health calculators. The evidence-based medicine movement, formalized by Gordon Guyatt and colleagues at McMaster University in the early 1990s, demanded that all health recommendations derive from systematically graded clinical evidence. The digital health era beginning in the 2000s brought these formulas to consumer devices, wearable sensors, and smartphone applications, expanding access to health self-monitoring on a global scale and enabling population-level data collection that continues to refine clinical reference ranges.
Frequently Asked Questions
Formula
Refeed Calories = TDEE x 1.05; Refeed Carbs = (Refeed Cal - Protein Cal - Reduced Fat Cal) / 4
Refeed calories are set at approximately 105% of estimated TDEE to provide a slight surplus. Protein remains constant from the cutting phase. Fat is reduced to 70% of cutting levels to make room for more carbs. All extra calories come from carbohydrates to maximize leptin restoration and glycogen replenishment.
Worked Examples
Example 1: Lean Male Refeed Day Setup
Problem: A 175 lb male at 14% body fat, cutting on 2,100 kcal (160g protein, 55g fat), has been dieting for 6 weeks.
Solution: Estimated TDEE: 2,100 + 500 = 2,600 kcal\nRefeed calories: 2,600 x 1.05 = 2,730 kcal\nProtein: 160g (same) = 640 kcal\nFat: 55 x 0.7 = 39g = 347 kcal\nRefeed carbs: (2,730 - 640 - 347) / 4 = 436g\nCutting carbs: (2,100 - 640 - 495) / 4 = 241g\nCarb increase: +195g | Calorie increase: +630 kcal\nFrequency: Every 5-7 days (14% BF)
Result: Refeed: 2,730 kcal | 160g protein | 39g fat | 436g carbs (+195g vs cutting)
Example 2: Female Competitor Refeed
Problem: A 130 lb female at 16% body fat, cutting on 1,500 kcal (130g protein, 40g fat), 8 weeks into prep.
Solution: Estimated TDEE: 1,500 + 500 = 2,000 kcal\nRefeed calories: 2,000 x 1.05 = 2,100 kcal\nProtein: 130g (same) = 520 kcal\nFat: 40 x 0.7 = 28g = 252 kcal\nRefeed carbs: (2,100 - 520 - 252) / 4 = 332g\nCutting carbs: (1,500 - 520 - 360) / 4 = 155g\nCarb increase: +177g | Calorie increase: +600 kcal\nFrequency: Every 7-10 days (16% BF)
Result: Refeed: 2,100 kcal | 130g protein | 28g fat | 332g carbs (+177g vs cutting)
Frequently Asked Questions
What is a refeed day and how does it differ from a cheat day?
A refeed day is a strategically planned increase in calorie intake, primarily through carbohydrates, during a fat loss phase. Unlike a cheat day where you eat anything without tracking, a refeed day has specific calorie and macro targets. The purpose is to temporarily restore leptin levels, replenish muscle glycogen, support thyroid function, and provide psychological relief from dieting. Refeed calories are typically set at or slightly above your total daily energy expenditure, with the increase coming almost entirely from carbohydrates while protein stays the same and fat is reduced. This controlled approach provides metabolic benefits without the excessive calorie surplus that cheat days often create.
How do refeed days help with fat loss?
Refeed days support continued fat loss by counteracting the hormonal and metabolic adaptations that occur during extended calorie restriction. The primary mechanism is restoring leptin levels, a hormone that decreases during dieting and signals your brain to reduce metabolic rate and increase hunger. Carbohydrate intake specifically boosts leptin more effectively than fat or protein. Refeeds also support thyroid hormone conversion from T4 to T3, maintaining metabolic rate. Additionally, they replenish depleted muscle glycogen stores, which improves training performance and allows you to maintain the exercise intensity needed for muscle preservation. The psychological break from restriction also improves long-term dietary adherence.
How often should you have a refeed day during a cut?
Refeed frequency depends primarily on your current body fat percentage and how long you have been dieting. Leaner individuals with body fat below 10 percent benefit from refeed days every 3 to 4 days because their leptin levels are more severely suppressed. Those at 10 to 15 percent body fat should refeed every 5 to 7 days. Individuals at 15 to 20 percent body fat can refeed every 7 to 10 days. Those above 20 percent generally only need a refeed every 10 to 14 days because they have sufficient body fat to maintain adequate leptin signaling. As your diet progresses and you get leaner, increase refeed frequency accordingly to prevent metabolic stalling.
Why should carbohydrates be the primary macro increased on a refeed day?
Carbohydrates are the most effective macronutrient for restoring leptin levels, which is the primary goal of a refeed day. Research shows that carbohydrate overfeeding increases circulating leptin by 28 percent within 24 hours, while fat overfeeding has minimal impact on leptin even at the same calorie level. Carbohydrates also replenish muscle glycogen stores that become depleted during calorie restriction, directly improving training performance. Additionally, carbs stimulate insulin release, which has anti-catabolic effects that help preserve muscle tissue. High carb intake also increases serotonin production, improving mood and reducing the psychological stress of dieting. This is why refeeds focus on carbs rather than simply eating more of everything.
What types of carbohydrates should you eat on a refeed day?
On a refeed day, prioritize complex carbohydrate sources that are low in fat to maximize glycogen replenishment without excessive calorie surplus. Excellent choices include white and brown rice, potatoes and sweet potatoes, pasta, bread, oatmeal, cereals, rice cakes, and fruits. These foods are carbohydrate-dense with minimal fat content, allowing you to hit high carb targets without dramatically overshooting calories. Avoid high-fat carb sources like pastries, pizza, ice cream, and fried foods because the fat adds significant calories without additional leptin-boosting benefit. The goal is high carbohydrate intake, not high calorie intake from mixed sources.
Should you reduce fat intake on refeed days?
Yes, reducing fat intake on refeed days is recommended to keep total calories controlled while maximizing carbohydrate intake. A typical approach is reducing fat to approximately 70 percent of your normal cutting day fat intake. Since fat has 9 calories per gram compared to 4 for carbohydrates, reducing fat by 15 to 20 grams frees up 135 to 180 calories that can be allocated to an additional 34 to 45 grams of carbohydrates. This trade allows higher carb intake for better leptin response without dramatically increasing total calories. Protein should remain unchanged on refeed days to continue supporting muscle preservation. The overall effect is a modest calorie increase with a large carbohydrate increase.
References
Reviewed by Rahul Singh, Health & Wellness Specialist · Editorial policy