Why use this calculator
Protein is the macronutrient with the clearest evidence behind it and the widest gap between official minimums and practical targets. The recommended dietary intake of around 0.8 grams per kilogram is the amount needed to avoid deficiency, not the amount that supports training, satiety or ageing well.
And repeating it to someone lifting weights or dieting is actively unhelpful. This calculator uses the ranges from sports nutrition research instead, adjusts them upward for older adults, and splits the total across meals, because when you eat protein affects how much of it is actually used for muscle repair rather than simply burned for energy.
How to use it
- Enter your body weight in kilograms or pounds.
- If you carry substantial excess fat, use a realistic target weight rather than current weight, since protein needs scale with lean mass rather than total mass.
- Choose the goal that matches what you are actually doing: needs rise with training and rise further during a calorie deficit, where protein is what protects muscle from being burned alongside fat.
- Set meals per day to how you actually eat, and enter your age, since the minimum is raised automatically from about 65 to counter age-related muscle loss.
What each result means
- Daily protein target
- The midpoint of the range for your goal. A practical daily figure rather than a minimum to avoid deficiency.
- Sensible range
- The published range for this goal. Anywhere inside it is reasonable; the midpoint is simply a default.
- Per meal
- Your target divided by your meals. Around 25 to 40 grams per meal is where muscle protein synthesis is effectively stimulated.
- Calories from protein
- How much of your daily energy the target represents, at about 4 calories per gram.
- Per kilogram of body weight
- The target expressed per kilogram, which is how sports nutrition research reports it.
- Roughly equivalent to
- A rough food equivalent so the gram figure means something. Real diets mix sources rather than relying on one.
- Age adjustment applied
- Shown when you are 65 or over, where the minimum is raised to counter age-related muscle loss.
The formula
The target is grams per kilogram of body weight multiplied by your weight, using ranges drawn from sports nutrition guidance: 0.8 to 1.2 for general health, 1.2 to 1.6 to maintain muscle, 1.4 to 1.8 for endurance training, 1.6 to 2.2 to build muscle, and 1.8 to 2.4 to lose fat while preserving muscle. The midpoint of the range is used as the headline figure. From age 65 the minimum is raised to 1.2 grams per kilogram. Protein provides about 4 calories per gram, and the per-meal figure is the daily total divided by your number of meals.
How this number is used in practice
Protein does more than build muscle, and the secondary benefits are what make a target easier to hold. It is the most satiating macronutrient, so a higher-protein diet reduces hunger at the same calorie level. Which is exactly the problem during a deficit. It also has the highest thermic effect, with roughly twenty to thirty per cent of its energy used in digestion compared with under ten per cent for carbohydrate and fat.
Distribution matters alongside the total. Muscle protein synthesis responds to a dose of roughly 25 to 40 grams and then plateaus, so three or four moderate servings across the day stimulate it more effectively than one very large serving at dinner. Most people eat very little protein at breakfast and a great deal at night, and simply shifting some earlier is the easiest change available.
Older adults are the group most often under-served by the official minimum. Age-related muscle loss accelerates from around 60, and both the absolute requirement and the dose needed to trigger muscle protein synthesis rise. Which is why guidance for older adults sits meaningfully above the general recommended intake, and why resistance training matters alongside the protein.
Worked examples
75 kg adult maintaining muscle, four meals a day
About 105 g of protein a day, or roughly 26 g per meal, at 1.4 g per kilogram.
80 kg adult building muscle, four meals
About 152 g a day, or 38 g per meal, at the 1.9 g per kilogram midpoint.
70 kg adult losing fat while keeping muscle, three meals
About 147 g a day, or 49 g per meal. The highest range, because protein protects muscle in a deficit.
When people use it
- Setting a protein target that matches your training rather than a minimum
- Protecting muscle while losing fat in a calorie deficit
- Planning how much protein to put in each meal
- Adjusting intake for an older adult countering muscle loss
- Checking whether a current diet is anywhere near an adequate target
Tips
- The 0.8 g per kg recommended intake prevents deficiency; it is not a target for anyone training.
- Spread protein across 3 to 4 meals of 25 to 40 g rather than concentrating it at dinner.
- In a calorie deficit, protein is what protects muscle. This is the goal with the highest requirement.
- If you carry substantial excess fat, base the target on a realistic target weight rather than current weight.
- Adults over 65 need more, both in total and per serving, to stimulate muscle protein synthesis.
- Plant-based diets need a slightly higher total and a wider mix of sources to cover all essential amino acids.
What it assumes, and where it stops being accurate
- Targets come from published sports nutrition ranges and are general guidance, not individual prescription.
- Body weight is used rather than lean mass, which overstates the target for anyone carrying substantial excess fat.
- The midpoint of each range is shown as the headline; anywhere in the range is reasonable.
- Protein quality and amino acid profile are not modelled, and plant sources generally need higher totals.
- Kidney disease, liver disease, pregnancy and some medications change protein requirements and need clinical advice.
- The food equivalents are rough averages and vary considerably between cuts, brands and cooking methods.
Terms used on this page
- Muscle protein synthesis
- The process of building new muscle protein, stimulated by protein intake and resistance training.
- Recommended dietary intake
- The amount sufficient to meet the needs of nearly all healthy people. A minimum, not a target.
- Leucine
- The essential amino acid most responsible for triggering muscle protein synthesis.
- Thermic effect of food
- Energy used digesting food; protein's is the highest of the three macronutrients.
Questions people ask
- How much protein do I need a day?
- It depends on what you are doing. Around 0.8 grams per kilogram of body weight prevents deficiency, 1.2 to 1.6 maintains muscle, 1.6 to 2.2 supports building it, and 1.8 to 2.4 protects muscle during fat loss. For a 75 kilogram adult that is roughly 60 grams at the minimum and 135 to 180 grams when training hard.
- Is the recommended dietary intake enough?
- It is enough to avoid deficiency in a sedentary adult, which is what it was designed for. It is not a target for anyone doing resistance training, losing weight, or over about 65, where research consistently supports substantially higher intakes for maintaining muscle and function.
- Can you eat too much protein?
- For healthy adults, intakes up to around 2 grams per kilogram are well tolerated in the research, and higher intakes have not been shown to damage healthy kidneys. People with existing kidney disease do need to restrict protein under medical supervision. The practical limit for most people is that protein displaces other foods and gets expensive.
- Does it matter when I eat protein?
- Distribution matters more than precise timing. Muscle protein synthesis responds to doses of roughly 25 to 40 grams and then plateaus, so three or four moderate servings work better than one very large one. The old idea of a narrow anabolic window straight after training has not held up; total daily intake and spread matter far more.
- Do I need protein powder?
- No, but it is convenient and usually cheaper per gram than most whole-food sources. Whole foods bring other nutrients with them and are more satiating. Powder is most useful for hitting a high target without excessive volume, for breakfast when appetite is low, or immediately after training when eating a meal is impractical.
- Is plant protein as good as animal protein?
- It can be, with attention to total and variety. Most plant sources are lower in one or more essential amino acids, particularly leucine, which drives muscle protein synthesis. Eating a range across the day covers the gaps, and a modestly higher total, around ten to twenty per cent more, is the usual recommendation for a plant-based diet.
Use this with
Protein Intake Calculator answers one part of the question. These pick up where it stops: Macronutrient Calculator, Calorie Calculator, BMR Calculator and One Rep Max Calculator.
Where these figures come from
This calculation is jurisdiction-neutral arithmetic. No country-specific rules are applied.
- NHMRC: nutrient reference values for protein. Recommended dietary intake for protein by age and sex
- Eat For Health: Australian Dietary Guidelines. Nutrient reference values including protein
Protein Intake Calculator produces an estimate for general information. It is not financial, tax, medical, legal or engineering advice. read the full disclaimer. Spotted a wrong number? Report it and it gets fixed. The form picks up this calculator and the inputs you used.