How much protein do you need?
Protein provides the amino acids your body uses to maintain and repair tissues. Your useful daily range depends on your activity, goals and individual circumstances. A basic population minimum and a target for someone doing strength training are not the same thing.
This tool uses goal-based ranges discussed in Dr Richie Kirwan’s Heracles nutrition course. It returns a range rather than suggesting that one exact gram target is right for everyone.
| Goal | Protein used by this tool |
|---|---|
| Maintain / active nutrition | 1.2–2.0 g/kg/day |
| Build muscle / strength | 1.6–2.2 g/kg/day |
| Fat loss with muscle retention | 1.8–2.5 g/kg/day |
These are planning ranges from the course, particularly relevant to active adults. Their upper ends are optional and are not minimum requirements. A general health goal with little training may not require the higher ranges.
Which body weight does it use?
By default, the nutrition reference is your current weight or the weight corresponding to BMI 25 at your height, whichever is lower. This follows the course’s worked example, which avoids very large protein targets at higher body weights. The result tells you the exact reference used.
This is a calculation aid, not an ideal-weight diagnosis or a weight-loss instruction. It may understate needs in a very muscular person. You can select current body weight instead if that is more appropriate, or seek individual advice.
Make it work across your day
Choose the number of meals that fits your routine. The calculator divides your daily range evenly between them as a practical guide, not a requirement for every meal. Your overall daily intake matters, and different meals can contribute different amounts.
Build meals around foods you enjoy: fish, meat, eggs, dairy, beans, lentils, tofu, tempeh or mycoprotein such as Quorn. A varied plant-based diet can also contribute useful protein. Supplements can be convenient but are not a requirement.
Protein is part of the whole plan
For fat loss, energy balance still matters. For muscle gain, training, recovery and sufficient energy matter alongside protein. Use the macro calculator to see how protein fits with fats and carbohydrate.
Kidney disease and some other health conditions can alter appropriate protein intake. If you have been given nutrition advice for a medical condition, use that advice rather than a general range.
Questions about this calculator
Do I need the top end of the range?
No. It is a range, not a minimum. Your training, goal, appetite and circumstances help determine what is practical.
Why is the reference weight lower than my current weight?
The default caps the calculation at the weight corresponding to BMI 25, following the course example. This avoids oversized targets at higher body weights. You can choose current weight where appropriate.
Can plant foods count towards my protein?
Yes. Beans, lentils, tofu, tempeh, mycoprotein and other plant foods can contribute. Variety and sufficient total intake matter.
Must every meal contain the same protein?
No. The per-meal result is an even distribution to make planning easier. It does not mean every meal must be identical.
Method and sources
Nutrition principles adapted from Dr Richie Kirwan’s Heracles course, Optimizing Your Nutrition, Modules 1 and 3. Calculator implementation and explanations by Heracles.