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Protein Calculator

Health

Calculate your daily protein target in grams from body weight and goal, using evidence-based g/kg ranges for muscle building, fat loss, and general fitness.

Reviewed by the thecalcu.com team · Last updated July 19, 2026

Body Weight
kg
30200
Activity Level / Goal

Daily Protein Target — Moderate Activity

—g/day
Protein Calories
—
kcal/day

What is a Protein?

A Protein Calculator estimates your daily protein target in grams based on your body weight and activity level or fitness goal, using the grams-per-kilogram (g/kg) approach favored by sports nutrition research. Unlike calculators that derive protein as a percentage of total calories, this tool sets protein directly from body weight, the method most dietitians and strength coaches actually use, since protein needs scale with lean body mass rather than total energy intake.

The calculator offers five activity/goal tiers, from sedentary (0.8 g/kg) up to fat loss (2.0–2.4 g/kg), reflecting how protein requirements shift dramatically based on training status and whether you're in a calorie deficit or surplus. It pairs naturally with the TDEE Calculator for total calorie planning and the Macro Calculator for a full protein/fat/carb breakdown.

Why Use a Protein Calculator?

Generic advice like "eat more protein" doesn't tell you how much is actually enough for your body size and goal, someone weighing 60 kg and someone weighing 100 kg have very different absolute protein needs even at the same activity level. This calculator translates evidence-based g/kg ranges into a specific gram target you can actually track.

It's especially useful when starting a new training phase, whether that's a muscle-building block requiring 1.6–2.2 g/kg, or a cutting phase where protein needs actually increase to 2.0–2.4 g/kg to protect lean mass during the deficit. Use it alongside the IIFYM Calculator if you want your fat and carb targets calculated around this same protein floor.

Who Should Use This Calculator?

Strength trainees and bodybuilders need reliable protein targets to support muscle growth, and this calculator's Muscle Building tier reflects the 1.6–2.2 g/kg range supported by resistance training research. People in a cutting phase should pay attention to the Fat Loss tier, since protein needs actually rise during a calorie deficit to protect muscle mass. General fitness enthusiasts who exercise casually but aren't training for performance can use the General Fitness or Moderate Activity tiers for more modest, realistic targets. Sedentary individuals starting a health journey can use the Sedentary tier as an appropriate baseline before increasing activity. Nutrition-conscious eaters who track macros can use this alongside the Macro Calculator to sanity-check whether their current protein intake matches evidence-based recommendations for their goal.

What Insights Does the Protein Calculator Give You?

Daily Protein Target is the primary result, your recommended protein intake in grams per day, calculated by multiplying your body weight by the g/kg figure associated with your selected activity level and goal. Protein Calories converts that gram target into calories (at 4 kcal per gram of protein), which is useful for understanding how much of your total daily calorie budget is allocated to protein, and for cross-checking against total calorie targets from tools like the TDEE Calculator.

How to use this Protein calculator

  1. Enter your Body Weight in kilograms using the slider or number input.
  2. Select your Activity Level / Goal from the dropdown, each option shows its associated g/kg range (e.g. "Muscle Building, 1.6–2.2 g/kg").
  3. Review the Daily Protein Target result, shown in grams per day.
  4. Check the Protein Calories figure to see how many calories that protein target represents.
  5. Compare this target against your current protein intake from a food tracking app to identify any gap.
  6. Recalculate if your body weight or training goal changes significantly.
Show formula & methodology ↓Show less ↑

Formula & Methodology

Protein target:

DailyProteinG = BodyWeight(kg) × g/kg multiplier

| Activity Level / Goal | g/kg used |
|---|---|
| Sedentary | 0.8 |
| General Fitness | 1.1 |
| Moderate Activity | 1.4 |
| Muscle Building | 1.9 |
| Fat Loss (preserve muscle) | 2.2 |

Protein calories:

ProteinCalories = DailyProteinG × 4

Worked example: A 70 kg person selecting "Muscle Building" (1.9 g/kg midpoint) gets a Daily Protein Target of 70 × 1.9 = 133g, which equals 133 × 4 = 532 protein calories per day.

Frequently Asked Questions

How much protein do I need per day?
Daily protein needs range from about 0.8 g/kg for sedentary adults up to 2.0–2.4 g/kg for people actively building muscle or preserving lean mass during a calorie deficit. The right number depends on your activity level and goal, someone doing regular strength training needs considerably more protein than someone who is largely sedentary. This calculator estimates your target using your body weight and selected activity/goal level.
Why is protein measured in grams per kilogram of body weight?
Protein needs scale with lean body mass and activity level rather than total calorie intake, which is why nutrition science expresses targets in grams per kilogram (g/kg) of body weight rather than as a fixed number or percentage of calories. This approach, used by sports nutrition researchers and dietitians, produces more individually accurate targets than a flat daily gram number that ignores body size.
Is 1g of protein per pound of body weight accurate?
The commonly cited '1g per pound' guideline is roughly equivalent to 2.2 g/kg, which sits within this calculator's Muscle Building and Fat Loss ranges and is a reasonable target for people in an active muscle-building or cutting phase. For general fitness or sedentary individuals, this amount is higher than necessary, the calculator's lower activity tiers (0.8–1.2 g/kg) are more appropriate for those groups.
Do I need more protein when losing weight?
Yes, protein needs increase during a calorie deficit, typically 2.0–2.4 g/kg, because higher protein intake helps preserve lean muscle mass while your body is in an energy deficit, which is essential for maintaining metabolic rate and body composition. This is why the Fat Loss option on this calculator carries the highest g/kg range of all five categories.
What is the difference between this and the Macro Calculator?
This calculator sets protein directly from body weight using evidence-based g/kg ranges, independent of total calorie intake. The [Macro Calculator](/macro-calculator/) instead derives protein as a percentage of your total daily calories (alongside fat and carbs), which can under- or over-allocate protein depending on your calorie target. Body-weight-based protein targets are generally considered more accurate for training-focused goals.
Can I eat too much protein?
For most healthy adults, protein intake up to around 2.5–3 g/kg is well within safe limits and shows no evidence of harm to kidney function in people without pre-existing kidney disease. Intake far beyond your calculated target simply displaces calories that could go toward carbs or fat, without providing additional muscle-building benefit beyond a certain point (generally accepted to be around 2.2 g/kg for most training goals).
How do I use the Protein Calculator?
Enter your **Body Weight** in kilograms using the slider or number field. Select your **Activity Level / Goal** from the dropdown, Sedentary, General Fitness, Moderate Activity, Muscle Building, or Fat Loss, each showing its associated g/kg range. The calculator immediately displays your Daily Protein Target in grams and the equivalent Protein Calories.
What is the difference between protein grams and protein calories?
Protein provides 4 calories per gram, so your Protein Calories figure is simply your Daily Protein Target multiplied by 4. This conversion is useful for checking how much of your total daily calorie budget protein represents, or for comparing against calorie targets from tools like the [TDEE Calculator](/tdee-calculator/).
Should athletes use a higher protein target than this calculator suggests?
For most strength and endurance athletes, the Muscle Building range (1.6–2.2 g/kg) covers typical needs well, and very few athletes require intake beyond 2.2–2.4 g/kg even during intense training blocks. Elite or specialized athletes working with a sports dietitian may have individualized targets that account for specific competition demands, but this calculator's ranges are appropriate for the vast majority of recreational and competitive athletes.
Does body fat percentage affect how much protein I need?
Yes, protein needs are more accurately based on lean body mass than total body weight, so a person with a higher body fat percentage technically needs somewhat less protein per kilogram of total weight than a leaner person at the same weight. This calculator uses total body weight for simplicity, which is a standard and widely used approximation, very lean or very high body-fat individuals may want to adjust slightly based on estimated lean mass.
How does protein intake relate to my overall calorie goal?
Your protein target from this calculator is one part of your total daily calorie and macro plan, use the [TDEE Calculator](/tdee-calculator/) to determine your total calorie needs, then subtract your protein calories (protein grams × 4) from that total to see how many calories remain for fat and carbohydrates. Tools like the [IIFYM Calculator](/iifym-calculator/) automate this entire process in one step using the same bodyweight-first protein approach.
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