This protein calculator tells you how much protein per day you need based on your body weight and what you are training for. The U.S. RDA is 0.8 grams per kilogram of body weight — enough to prevent deficiency in sedentary adults — but research consistently shows that active people, lifters, and anyone dieting benefit from considerably more.
Enter your weight, pick the goal that matches your routine, and press Calculate. You will get a single daily gram target, the full research-supported range for your goal, and a practical per-meal amount so you can actually hit the number at the table.
How Protein Needs Are Calculated
Protein requirements scale with body weight, so all recommendations are expressed in grams per kilogram (g/kg) per day. This calculator uses these research-backed values:
- Sedentary: 0.8 g/kg — the RDA, a minimum to prevent deficiency
- Active (regular exercise): 1.2–1.4 g/kg, target 1.3
- Strength training / building muscle: 1.6–2.2 g/kg, target 1.8
- Cutting (dieting while keeping muscle): 2.0–2.4 g/kg, target 2.2
- Endurance training: 1.2–1.6 g/kg, target 1.4
The strength-training range comes from a 2018 meta-analysis of 49 trials showing muscle gains plateau around 1.6 g/kg, with 2.2 g/kg as the upper confidence bound. Cutting targets are higher because protein preserves lean mass and blunts hunger while calories are restricted.
High-Protein Foods to Hit Your Target
Knowing your number only helps if you can build meals around it. Protein per 100 g (about 3.5 oz) of common foods:
- Chicken breast (cooked): 31 g
- Lean beef (cooked): 26 g
- Salmon: 25 g
- Canned tuna: 24 g
- Greek yogurt (nonfat): 10 g
- Eggs: 13 g (about 6 g per large egg)
- Firm tofu: 14 g
- Cooked lentils: 9 g
- Cottage cheese: 11 g
- Whey protein powder: 20–25 g per scoop
Aim for 25–40 g per meal across 3–5 meals. Research on muscle protein synthesis suggests roughly 0.4 g/kg per meal is the point of diminishing returns, which is why spreading intake beats loading it all at dinner.
Example: 165 lb Lifter
A 165 lb (75 kg) person who strength trains three to four times per week selects the strength-training goal at 1.8 g/kg.
Daily target: 75 × 1.8 = 135 g of protein per day. Range: 75 × 1.6 to 75 × 2.2 = 120–165 g/day. Per meal over 4 meals: about 34 g.
A sample day hitting 135 g: 3 eggs and Greek yogurt at breakfast (33 g), a chicken breast salad at lunch (38 g), a whey shake after training (24 g), and salmon with lentils at dinner (40 g). If the same person starts a fat-loss diet, the cutting target of 2.2 g/kg raises the goal to about 165 g/day.
Frequently Asked Questions
How much protein do I need a day?
The RDA is 0.8 g per kg of body weight (about 0.36 g per lb) — roughly 60 g for a 165 lb adult. If you exercise regularly, aim for 1.2–1.4 g/kg; if you lift weights to build muscle, 1.6–2.2 g/kg; and if you are dieting to lose fat, around 2.2 g/kg to protect muscle.
Is 100 grams of protein a day enough?
For a 150 lb (68 kg) person, 100 g equals about 1.5 g/kg — plenty for general fitness and adequate for most lifters. For someone 200 lbs or heavier who trains seriously or is cutting, 100 g falls short of the 1.6–2.2 g/kg range, and 145–200 g would be more appropriate.
Can I eat too much protein?
For healthy adults, intakes up to about 3 g/kg have shown no harm to kidney or liver function in controlled studies. There is little benefit above 2.2 g/kg for muscle growth, however, and extra protein calories still count toward weight gain. People with existing kidney disease should follow medical advice.
Should I calculate protein from body weight or lean mass?
Total body weight works well for most people and is what this calculator uses. If you carry significant excess fat (BMI over 30), calculating from your goal weight or lean body mass avoids inflated targets — a 280 lb person aiming for 200 lbs can sensibly target protein for 200 lbs.
How much protein should I eat per meal?
About 25–40 g per meal, or roughly 0.4 g per kg of body weight, maximizes muscle protein synthesis at each sitting. Your body still uses protein beyond that amount, but spreading your daily total across 3–5 meals produces better muscle-building results than one or two huge servings.