Protein Calculator

Find your daily protein target — in grams — based on body weight, activity, and goal. Whether you're building muscle, cutting fat, or just trying to eat well, get a target that actually fits.

Your Details

Results update live as you type.

weight
lbs
lbs
weekly
target
Energy density4 kcal/g
Live calculation

Recommended daily protein

125 g

General health · 1.0–1.4 g/kg · 500 kcal from protein

RDA minimum

58 g

Upper end

145 g

Per kg of bw

1.2 g/kg

Calories

500 kcal

Per meal (4 meals) Meal split
GoalRange (g/kg)Daily targetYour pick

The Formula

How this calculator works

We multiply your body weight (in kg) by a grams-per-kilogram coefficient that depends on your goal — fat loss and muscle building push it higher, sedentary maintenance keeps it close to the RDA of 0.8 g/kg.

The recommended value sits at the midpoint of the range for your goal. We scale the range slightly based on activity, since active bodies need more protein for repair and adaptation.

Protein Math

Protein (g) = body weight (kg) × g/kg coefficient RDA:  0.8 × kg Muscle gain:  1.6–2.2 × kg Fat loss:  1.4–1.8 × kg Endurance:  1.2–1.6 × kg
kg body weight (convert lbs ÷ 2.2046)
g/kg grams per kilo of bodyweight
4 kcal per gram of protein
RDA minimum for sedentary adults

About This Tool

What Is a Protein Calculator?

A protein calculator turns your body weight, activity level, and goal into a concrete daily target in grams. Protein is the most under-eaten macro for most people — yet it's the one that drives muscle growth, recovery, and satiety.

The official RDA of 0.8 g/kg is a minimum — set to prevent deficiency in sedentary adults. Active people, lifters, dieters, and older adults all benefit from 1.2–2.2 g/kg, with diminishing returns above 2.2.

This tool uses ranges from peer-reviewed sports nutrition guidelines: 1.6–2.2 g/kg for muscle building, 1.4–1.8 g/kg for fat loss (to preserve lean mass), and 1.2–1.6 g/kg for endurance training. Adjust for your goal and re-check every few months as body weight changes.

Instant Live Results

Protein target updates the moment you change a value.

Goal-Based Ranges

Build muscle, lose fat, run further, or just eat well.

Per-Meal Math

See your daily target split across 4 meals automatically.

100% Free & Private

No account needed. All maths runs in your browser.

Backed by Research

Ranges from ISSN and AND sports nutrition position stands.

lbs or kg

Switch between imperial and metric instantly.

How to Use This
Protein Calculator

Three inputs, four numbers — your protein plan in under a minute.

1

Pick Your Units

Choose lbs or kg. We convert internally to kilograms because protein guidelines are kg-based.

2

Enter Body Weight

Use a recent, morning-before-eating weight for the most stable reading.

3

Set Activity Level

Active bodies need more protein. Pick the closest match — sedentary, light, moderate, or athlete.

4

Choose a Goal

Muscle, fat loss, endurance, or general health — each shifts the gram-per-kilo range.

5

Split Across Meals

Aim for 25–40 g per meal across 3–5 meals. This maximises muscle protein synthesis.

6

Track & Adjust

If muscle, energy, or weight aren't moving the way you want after 4 weeks, re-check the goal setting.

Frequently Asked Questions

Everything you need to know about daily protein intake.

The RDA (Recommended Dietary Allowance) is 0.8 g/kg of body weight per day. That's the minimum to prevent deficiency in sedentary adults — not an optimal target. Active people typically need 1.2–2.2 g/kg.

For healthy adults, intakes up to 3.5 g/kg/day appear safe in research. Very high intakes may stress kidneys in people with existing kidney disease. Check with a doctor if you have a kidney condition.

1.6–2.2 g/kg of body weight per day, split across 3–5 meals of 25–40 g each, alongside progressive resistance training. Going beyond 2.2 g/kg shows diminishing returns.

1.4–1.8 g/kg of body weight per day. Higher protein during a calorie deficit preserves lean muscle, increases satiety (you feel fuller for longer), and has a higher thermic effect than carbs or fat.

Animal sources: chicken, fish, lean beef, eggs, Greek yoghurt, cottage cheese. Plant sources: tofu, tempeh, lentils, chickpeas, edamame, seitan. Whey, casein, and plant-based powders are practical for hitting targets.

Total daily intake matters most. An anabolic "window" exists but is wider than once thought (~4 hours pre/post). Eating 25–40 g of protein within a few hours of training is a good practical rule.

Animal proteins are complete (contain all essential amino acids in good ratios) and generally higher in leucine. Plant eaters can match results by eating more total protein and combining sources (rice + beans, etc.) to cover the amino acid spectrum.