Free calculator
Protein Calculator
A practical protein planning estimate.
Before you use the calculator
What is this calculator for?
Protein is essential for maintaining muscle, supporting recovery and helping you feel satisfied after meals. A protein calculator estimates a daily intake based on your body weight, activity and goals. It can be particularly useful during weight loss because preserving lean mass matters — especially if you are eating less overall or using a weight-management treatment that reduces appetite.
What it measures
- Body weight
- Activity level
- Goal or context
- Estimated daily protein range
Why it is here
It can give you a sensible protein target to aim around rather than guessing or relying on gym-bro numbers that may be far more than you need.
What this result cannot tell you
No calculator can understand everything about you. Important limitations include:
- Kidney disease or other conditions requiring individual advice
- Your total calorie intake
- Protein quality and food choices
- Meal timing preferences
- How much you can comfortably eat
- Individual clinical advice
You do not need to live on shakes and chicken breasts. A useful protein target should fit normal food, normal meals and normal life.
How to use the result sensibly
Use the number as a starting point. Look at the overall trend, how you feel, what is happening with your waist, movement, sleep, blood pressure and other relevant health markers. Where the result is unexpected, concerning or difficult to interpret, a qualified healthcare professional can put it into context.
Industry-standard does not mean individually perfect. These calculators use recognised methods because they are useful, not because they can define a person. Results are informational, subjective in context and open to interpretation.
What should I do next?
How this works, limitations & evidence
Interpretation, limitations & evidence
Understand the result — then decide what matters
The calculator multiplies body weight by the planning level you select. That is useful for building a target, but the number becomes less reliable when body weight is very high, because protein requirements do not always scale perfectly with excess body fat.
What does the UK reference intake say?
The UK adult reference nutrient intake for protein is based on roughly 0.75 g per kg of body weight per day for generally healthy adults. That is a population reference for adequacy — not necessarily an ideal target for somebody dieting hard, getting older or resistance training.
Why this calculator starts higher
The available planning levels — 1.2, 1.6 and 2.0 g/kg — are deliberately presented as planning options rather than medical prescriptions. Higher protein intakes are commonly used during calorie restriction and strength training to support satiety and lean tissue.
What if the result looks enormous?
If a straight current-weight calculation produces a very large target that is difficult to eat or medically inappropriate, do not force it. A dietitian may use goal weight, reference weight or another method.
Spread protein across the day
For many people, three or four protein opportunities are easier than trying to rescue the target at 9pm. A practical day might include eggs or yoghurt at breakfast, chicken, tuna or beans at lunch, a protein-led dinner and one protein-rich snack.
Consistency across ordinary meals is generally more useful than chasing a perfect number with late-night shakes.
Protein on Mounjaro or Wegovy
Reduced appetite can make it easier to miss protein altogether. Guy’s and St Thomas’ NHS uses practical targets around 80–100 g/day for many patients taking weight-loss medicines, alongside individual advice.
Food first — shakes optional
Protein shakes can be convenient but they are not required. Meat, fish, eggs, yoghurt, cottage cheese, beans, lentils, tofu and meat alternatives can all contribute. The target should fit normal food, your calorie intake and any medical advice you have been given.
Common questions
Is more protein always better?
No. Once needs are met, ever-higher intakes do not automatically produce more fat loss or muscle.
Do I need protein powder?
No. It is convenience, not a requirement.
What if I have kidney disease?
Get individual clinical or dietetic advice before adopting a high-protein target.
What should I use next?
Sources & methodology
We use UK guidance and primary research where appropriate, and disclose when a result is an estimate rather than a clinical threshold.
Use this page as information, not judgement. The best next step is the one that actually fits your health, your life and what you are ready to change.
Written and editorially reviewed by the Shift Some Timber. Editorial review is not clinical review. Health content is checked against recognised UK guidance and primary sources where appropriate.
Last reviewed: 8 August 2026. This page is informational and does not replace individual medical advice.