The formula
How it works
Estimate how much protein you should eat each day based on your body weight and goal. Needs range from about 0.8 g per kilogram for a sedentary adult up to 2 g for someone building muscle.
FAQ
Can I eat too much protein?
For healthy people, moderately high protein is safe and helps with fullness and muscle. Very high intakes have little extra benefit, and anyone with kidney problems should get medical advice before raising protein a lot.
Should I use total or lean body weight?
These figures use total body weight, which works well for most people. Very overweight individuals sometimes base protein on lean mass or ideal weight instead, to avoid overestimating.
Why does the protein factor change with activity level?
Harder training and muscle-building both increase the rate of muscle protein breakdown and repair, so more protein is needed to keep up. A sedentary adult only needs enough to cover everyday losses, while an athlete or someone building muscle needs extra to support the added workload.
Does it matter if my protein comes from animal or plant sources?
Animal proteins are complete, supplying all essential amino acids in one food, while many plant proteins are lower in one or more of them. Eating a variety of plant sources across the day — beans, grains, soy — easily covers the gap.
Do I need to eat protein at every meal?
Spreading protein evenly across three or four meals helps your body use it for muscle repair more effectively than getting most of it in one sitting. Aiming for roughly equal portions, as shown in the per-meal figure, is a simple way to do this.
Do protein needs change with age?
Older adults often need more protein than younger adults at the same activity level, since ageing reduces how efficiently the body builds muscle from a given amount. Many guidelines suggest nudging toward the higher end of the range past age 65.
Does the type of exercise affect how much protein I need?
Strength and resistance training generally demand more protein for muscle repair than pure endurance work, though endurance athletes still need more than sedentary people. Picking the activity option that best matches your main training style gives the most accurate estimate.
About the protein calculator
This calculator estimates your daily protein target from your body weight and how active you are. Protein builds and repairs muscle, keeps you feeling full, and preserves lean tissue when you are losing weight, so getting enough matters — especially if you train. Because needs scale with body size and activity, the calculator uses grams per kilogram to give a personal figure rather than a one-size-fits-all number.
How to use it
Enter your body weight, choose kilograms or pounds, and pick the option that matches your goal — from sedentary through to building muscle. The calculator returns your recommended daily protein in grams. For example, an active 80 kg adult at 1.2 g per kilogram needs about 96 g of protein a day, while someone building muscle at 2 g per kilogram would aim for 160 g. Spread it across meals for the best effect.
The formula
The target is your weight in kilograms times a factor: . The factor ranges from about 0.8 g per kg for a sedentary adult — the basic requirement — up to 1.6–2.0 g per kg for athletes and people building muscle or dieting hard. Pounds are converted to kilograms first. Each gram of protein also provides 4 calories, which feeds into your overall macro split.
Where it is used
Athletes and gym-goers use it to make sure they eat enough to build and keep muscle, and dieters use a higher intake to hold onto lean tissue while losing fat. Dietitians set protein targets for recovery, ageing and certain medical conditions, and it feeds directly into meal planning and macro tracking. It is one of the most useful numbers for anyone serious about training or body composition.