Get your protein right — it changes everything
Protein is the most important macronutrient for body composition. Whether your goal is fat loss, muscle gain, or simply staying healthy — hitting your protein target is the single most impactful dietary habit you can build. This calculator uses research-backed multipliers so you get a number you can actually act on today.
What Is a Protein Calculator?
A protein calculator estimates how many grams of protein your body needs each day based on your weight, activity level, and health goal. Unlike one-size-fits-all recommendations, this tool adjusts for whether you're trying to lose fat while preserving muscle, build lean mass, or fuel endurance performance.
The RDA (Recommended Dietary Allowance) for protein in sedentary adults is just 0.8 g/kg — but this is the minimum to avoid deficiency, not the optimal amount for an active person. Research consistently shows that active individuals, especially those training for strength or body composition, benefit significantly from 1.6–2.2 g/kg or more.
How to Use This Protein Calculator
- Enter your body weight: In kg or lbs — this is the main driver of your protein target.
- Select your activity level: The more you train, the more protein your muscles need for repair and growth.
- Choose your primary goal: Muscle gain, fat loss, maintenance, or athletic performance each use a different multiplier.
- Select your diet type: Vegans and vegetarians get an adjusted target to account for lower digestibility of plant protein.
- Choose meals per day: See exactly how much protein to aim for at each meal.
- (Optional) Enter body fat %: If known, the tool calculates protein based on lean body mass instead of total weight — a more precise method.
How Protein Needs Are Calculated
📐 The formula
Daily Protein (g) = Body Weight (kg) × Multiplier (g/kg)
The multiplier varies by goal. Fat loss uses 1.8–2.4 g/kg to preserve muscle during a deficit. Muscle gain uses 1.6–2.2 g/kg. Maintenance uses 1.2–1.6 g/kg. Athletes use 1.6–2.0 g/kg.
🌱 Vegan/Vegetarian adjustment
Plant proteins have lower digestibility and a less complete amino acid profile compared to animal proteins. To compensate, a +10% adjustment for vegetarians and +15% for vegans is applied — consistent with guidance from sports nutrition bodies.
🧬 Lean Body Mass method
If you enter body fat %, your protein is calculated from lean body mass (LBM) — total weight minus fat. This is more accurate for body composition goals since fat mass doesn't require protein for maintenance.
🍽️ Per-meal distribution
Spreading protein evenly across 3–5 meals (~0.4 g/kg per meal) maximises muscle protein synthesis. This calculator divides your daily target by your chosen meal frequency.
Protein Intake Reference by Goal (g/kg Body Weight)
| Goal / Population | Activity Level | Recommended Range (g/kg/day) |
|---|---|---|
| Sedentary adult (baseline) | Little/no exercise | 0.8 – 1.0 g/kg |
| General health / Maintenance | Light–Moderate | 1.2 – 1.6 g/kg |
| Fat Loss (muscle preservation) | Moderate–Active | 1.8 – 2.4 g/kg |
| Muscle Gain / Hypertrophy | Active–Very Active | 1.6 – 2.2 g/kg |
| Endurance Athletes | Heavy Training | 1.4 – 1.8 g/kg |
| Strength / Power Athletes | Intense Training | 1.6 – 2.2 g/kg |
| Older Adults (65+) | Any | 1.2 – 1.6 g/kg (minimum) |
| Vegan / Vegetarian (adjust +10–15%) | Any | +10–15% above target |
Sources: ISSN Position Stand on Protein (2017), ACSM/AND/DC Joint Position Statement, and general sports nutrition literature. Individual needs may vary.
Best High-Protein Foods (Quick Reference)
🥩 Animal-Based (Top Sources)
- Chicken breast — ~31 g per 100 g
- Canned tuna — ~30 g per 100 g
- Eggs — ~13 g per 100 g (2 large = ~12 g)
- Greek yogurt — ~10 g per 100 g
- Cottage cheese — ~11 g per 100 g
- Salmon — ~25 g per 100 g
- Lean beef mince — ~26 g per 100 g
🌱 Plant-Based (Top Sources)
- Tempeh — ~19 g per 100 g
- Tofu (firm) — ~17 g per 100 g
- Lentils (cooked) — ~9 g per 100 g
- Edamame — ~11 g per 100 g
- Black beans — ~8.9 g per 100 g
- Seitan (wheat gluten) — ~25 g per 100 g
- Hemp seeds — ~31 g per 100 g
🥤 Convenient Supplements
- Whey protein powder — ~24 g per scoop
- Casein protein — ~24 g per scoop (slow-digesting)
- Pea protein — ~21 g per scoop (vegan)
- Rice protein — ~22 g per scoop (vegan)
- Soy protein isolate — ~27 g per scoop
- Protein bar — 15–25 g per bar (varies)
💡 Tip: Prioritise whole food protein sources first — use supplements only to fill gaps when whole foods aren't practical.
Protein Timing — Does It Matter?
Research shows that while total daily protein intake is the most important factor, how you distribute protein across the day also matters — particularly for muscle building.
⏰ Spread it out (most important)
Aim for roughly 0.4 g/kg per meal across 3–5 meals. This consistently maximises muscle protein synthesis compared to having most of your protein in one or two large meals.
🏋️ Post-workout protein
Having ~20–40 g of protein within 1–2 hours after training supports muscle recovery. The "anabolic window" is wider than once thought, but post-workout protein is still a practical habit.
🌙 Pre-sleep protein
40 g of casein protein before sleep has been shown to increase overnight muscle protein synthesis. A practical option for athletes in heavy training phases.
🌅 Breakfast protein
A high-protein breakfast (30–40 g) helps hit your daily target and reduces mid-morning hunger — which supports body composition goals via better appetite control throughout the day.