Calculate your optimal daily and per-meal protein intake for muscle building, maintenance, or fat loss
This calculator provides estimates only. Consult your GP or a healthcare professional for personalised advice.
Protein is the single most important macronutrient for building and maintaining muscle mass. Whether you are training to build muscle, trying to preserve muscle during a fat loss phase, or simply maintaining your current physique, getting the right amount of protein each day is essential. However, the optimal amount varies significantly depending on your body weight, your fitness goal, and your body composition. This muscle protein calculator uses evidence-based recommendations from the International Society of Sports Nutrition (ISSN) and the British Nutrition Foundation to provide a personalised daily protein target. It calculates your minimum, optimal, and maximum protein intake in grams per day, breaks it down into per-meal amounts based on how many meals you eat, and provides a post-workout protein recommendation. For those with higher body fat percentages, the calculator can optionally base the recommendation on lean body mass rather than total body weight. This provides a more accurate target because adipose tissue (body fat) does not require the same protein support as lean tissue. Simply enter your body fat percentage in the advanced options to activate this feature.
To calculate your optimal protein intake for muscle: 1. Enter your body weight in kilograms. If you know your weight in stones, multiply by 6.35 to convert. For example, 12 stone = 76.2 kg, 14 stone = 88.9 kg. 2. Select your primary goal from the dropdown: - Maintain Muscle: for those happy with their current physique (0.8 to 1.2 g/kg) - Build Muscle: for those in a muscle-building phase with resistance training (1.6 to 2.2 g/kg) - Fat Loss (Preserve Muscle): for those in a calorie deficit wanting to keep muscle (1.8 to 2.4 g/kg) - Endurance Athlete: for runners, cyclists, and other endurance sports (1.2 to 1.6 g/kg) 3. Enter the number of meals you eat per day (2 to 6). The calculator divides your optimal daily protein evenly across meals to determine a per-meal target. 4. Optionally, enter your body fat percentage in the advanced options. If provided, the calculator bases its recommendation on your lean body mass instead of total weight, which gives a more precise target for individuals with higher body fat. 5. Review your results. The calculator shows your daily protein range (minimum, optimal, maximum), per-meal protein target, and a post-workout recommendation for the 2-hour window after training.
The calculator uses evidence-based protein multiplier ranges for each goal: - Maintain Muscle: 0.8 to 1.2 grams per kilogram of body weight per day - Build Muscle: 1.6 to 2.2 grams per kilogram per day - Fat Loss (Preserve Muscle): 1.8 to 2.4 grams per kilogram per day - Endurance Athlete: 1.2 to 1.6 grams per kilogram per day The daily minimum uses the lower end of the range, the daily maximum uses the upper end, and the optimal recommendation uses the midpoint: Daily Optimal = Body Weight (kg) x (Range Low + Range High) / 2 Per-Meal Protein = Daily Optimal / Number of Meals The fat loss range is intentionally higher than the muscle-building range. When you are in a calorie deficit, your body is more likely to break down muscle tissue for energy. Higher protein intake during a cut helps signal to the body that muscle tissue should be preserved. Research from the ISSN supports intakes of 1.8 to 2.4 g/kg during energy restriction. If body fat percentage is provided, the calculator first computes lean body mass: Lean Body Mass = Total Weight x (1 - Body Fat % / 100) All protein calculations are then based on lean body mass instead of total weight. This adjustment is particularly useful for individuals with body fat above 25% (men) or 35% (women), as excess adipose tissue does not require additional protein. The post-workout recommendation of 0.4 to 0.55 g/kg within 2 hours of training is based on research showing that this dose maximally stimulates muscle protein synthesis during the recovery window.
Inputs: Weight: 75 kg, Goal: Build Muscle, Meals: 4, Body Fat: not entered
Inputs: Weight: 60 kg, Goal: Maintain Muscle, Meals: 3, Body Fat: not entered
Inputs: Weight: 90 kg, Goal: Build Muscle, Meals: 4, Body Fat: 20%
These protein recommendations are based on current sports nutrition research and are intended for healthy adults engaged in regular physical activity. If you have kidney disease, liver disease, or any medical condition affecting protein metabolism, consult your GP or a specialist before following high-protein dietary recommendations. The British Nutrition Foundation notes that most UK adults already consume adequate protein for general health (around 0.75 g/kg), but those engaged in resistance training or endurance sport typically need more. Good UK protein sources include chicken breast (31g per 100g), eggs (6g each), Greek yoghurt (10g per 100g), tinned tuna (25g per 100g), cottage cheese (11g per 100g), lentils (9g per 100g cooked), and whey protein powder (20-25g per scoop). Spreading protein intake across multiple meals throughout the day is more effective for muscle protein synthesis than consuming a large amount in a single meal.