The Protein Calculator estimates your daily protein target as a range in grams, from your body weight, activity level, and goal: maintain, build muscle, or lose fat. Enter weight in kilograms or pounds and it returns a minimum, a maximum, and a midpoint "optimal" figure, because the honest answer to "how much protein" is a range, not a point.
How It Works
The calculator multiplies body weight in kilograms by an activity-based range of grams per kilogram: sedentary 0.8 to 1.0, lightly active 1.0 to 1.2, moderately active 1.2 to 1.6, active 1.6 to 2.0, and very active 1.8 to 2.2. The goal then raises the floor where the evidence says it matters: muscle gain lifts the range to at least 1.6 to 2.2, and fat loss to at least 1.8 to 2.4, because protein's job in a deficit is defending lean mass while calories are scarce. The reported optimum is the midpoint of the final range.
Parameters
| Input | Required | Meaning | |---|---|---| | Weight | Yes | Kilograms or pounds (converted at 2.20462 lb per kg) | | Activity level | Yes | Sedentary, light, moderate, active, or very active | | Goal | Yes | Maintain, muscle gain, or fat loss |
Worked examples
A 70 kg moderately active person maintaining weight gets 1.2 to 1.6 g/kg: 84 to 112 g a day, midpoint 98 g. An 80 kg sedentary person aiming at fat loss has the goal override applied: the sedentary range of 0.8 to 1.0 is lifted to 1.8 to 2.4, giving 144 to 192 g, midpoint 168 g. That second example surprises people, and it is the calculator's most valuable output: the less you train and the deeper the deficit, the more protein does the work of keeping the weight lost as fat rather than muscle.
How the range compares with official guidance
The sedentary floor of 0.8 g/kg is the WHO/RDA minimum for generally healthy adults, set to prevent deficiency, not to optimize anything. Sports-nutrition position stands cluster around 1.4 to 2.0 g/kg for building and maintaining muscle with training, and meta-analyses of fat-loss studies support the higher intakes this calculator assigns to the fat-loss goal. Intakes at the top of these ranges have a wide safety margin in healthy adults; people with kidney disease or other conditions affecting protein metabolism should set targets with their clinician instead.
Hitting the number in real meals
Divide the target across meals: muscle protein synthesis responds best to roughly even distribution, so 100 g lands better as four 25 g servings than as a 70 g dinner and scraps. Anchor each meal to a palm-to-fist-sized portion of a protein food (Greek yogurt, eggs, tofu, tempeh, fish, poultry, lean meat, or a protein shake when whole food is impractical), each contributing roughly 20 to 40 g. Vegetarian diets reach the same totals with deliberate combining across the day; the calculator's target does not change, only the shopping list does.
Limitations
The range is driven by total body weight. For people with obesity, targets based on actual weight can overshoot needs substantially; using goal weight or lean mass as the input weight is the common clinical adjustment, and entering that adjusted figure here is reasonable. The calculator does not account for age-related anabolic resistance (older adults often benefit from the upper half of a range), pregnancy, or medical conditions.
Frequently Asked Questions
Is more protein always better?
No. Beyond the top of the evidence-based ranges, additional protein adds calories without adding measurable muscle or satiety benefit for most people. The maximum this calculator returns, 2.4 g/kg in a fat-loss context, is a ceiling, not a target to exceed.
Should I use my current weight or goal weight?
Current weight for maintenance and muscle gain. In a fat-loss phase with a large amount to lose, goal weight (or lean-mass estimates) gives a more sensible figure than multiplying a high body weight by 2.4.
Does protein timing matter?
Total daily intake is the first-order variable. Even distribution across three to four meals is a reasonable second-order refinement; the much-marketed narrow post-workout window matters far less than simply eating enough across the day.