What this calculator does
Protein needs are usually expressed per kilogram of body weight, because a larger body has more tissue to maintain. The official minimum is 0.8 g/kg, which is set to prevent deficiency rather than to support training.
Activity raises the figure considerably. For a 75 kg adult the RDA gives 60 g a day, while regular exercise puts the target nearer 105 g and strength training around 135 g.
The formula
Body weight in kilograms is multiplied by a factor for the activity level selected, from 0.8 for the sedentary minimum up to 1.8 for strength training.
| Term | Meaning |
|---|---|
| RDA | The recommended dietary allowance of 0.8 g/kg, a minimum to prevent deficiency. |
| g/kg | Grams of protein per kilogram of body weight, the standard way targets are expressed. |
| Protein factor | The multiplier applied to body weight, rising with training load. |
The inputs explained
| Field | What to enter |
|---|---|
| Body weight (kg) | Body weight in kilograms. |
| Activity level | Activity level, which selects the grams-per-kilogram factor applied. |
When to use it
Planning meals around a training programme
Higher training loads raise protein needs well above the general population minimum.
Checking whether current intake is adequate
Comparing what you actually eat against the target shows the size of any gap.
Understanding published guidance
The RDA and the sports nutrition figures differ because they answer different questions.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
What does each activity level require?
The same body weight at four activity levels.
| Activity level | Daily protein target | RDA minimum (0.8 g/kg) |
|---|---|---|
| Sedentary (0.8 g/kg) | 60 g/day | 60 g/day |
| Light (1.0 g/kg) | 75 g/day | 60 g/day |
| Regular exercise (1.4 g/kg) | 105 g/day | 60 g/day |
| Strength training (1.8 g/kg) | 135 g/day | 60 g/day |
Questions
Is the RDA enough?
It is enough to prevent deficiency in most healthy adults, which is what it was set to do. It was never intended as an optimum for people who train, and most sports nutrition guidance recommends considerably more.
Can you eat too much protein?
For healthy adults, intakes well above these figures have not been shown to cause harm in the research, though they displace other nutrients if total calories are fixed. Anyone with kidney disease should follow their clinician's advice rather than general guidance.
Should the target use total or lean body weight?
Both conventions exist. Using lean body mass avoids over-estimating for people carrying more fat, which matters most at the higher end of the body weight range. The difference is small for most people.
Does timing matter?
Spreading protein across meals appears to support muscle protein synthesis better than concentrating it in one sitting, but total daily intake is the larger factor by some margin.
For the calorie target this sits inside, see the TDEE calculator. For splitting calories across macronutrients, see the macro calculator.