Free Protein Calculator
Calculate how much protein you need per day based on your weight, your goal (muscle gain, weight loss, or maintenance), and whether you're on a GLP-1 medication.
Medical Disclaimer
This calculator provides general nutritional guidance based on scientific research. Before making any significant changes to your diet or protein intake, especially if you have existing health conditions, kidney problems, or are pregnant or breastfeeding, please consult with a qualified healthcare provider, registered dietitian, or your doctor. Individual needs may vary based on your specific health circumstances.
Why Your Protein Goal Is Unique
Everyone's protein requirements are different. Your optimal daily protein intake depends on two factors: your body weight and your fitness goal. Our calculator uses the same science-backed formula as the Protein Pal app to give you a personalized protein goal.
All calculations are done in canonical grams per kilogram. If you enter your weight in pounds we convert it first (1lb = 0.45359237kg) so the kg and lbs paths can never drift apart.
The Science Behind the Numbers
Maintenance: 0.83g/kg (0.38g/lb)
If your goal is general health and maintaining your current muscle mass, 0.83g/kg of body weight (0.38g/lb) is sufficient. This is the WHO Recommended Daily Allowance for protein and provides enough to maintain nitrogen balance and support overall health (WHO/FAO/UNU, 2007).
Weight Loss: 1.2g/kg (0.54g/lb)
When in a calorie deficit for weight loss, higher protein intake helps preserve lean muscle mass. 1.2g/kg (0.54g/lb) is the lower bound supported by the literature for lean-mass preservation in weight loss, as summarised in a 2016 review in Nutrition Reviews (Cava et al., 2017, Nutrition Reviews).
Muscle Gain: 1.6g/kg (0.73g/lb)
For building muscle, the evidence consistently points to 1.6g/kg (0.73g/lb) as the optimal intake. A meta-analysis of 49 studies in the British Journal of Sports Medicine (2018) identified this as the point of diminishing returns for muscle protein synthesis during resistance training (Morton et al., 2018, BJSM).
GLP-1 Medications: 1.2g/kg Minimum
If you're taking GLP-1 receptor agonist medications like semaglutide (Ozempic, Wegovy) or tirzepatide (Mounjaro), the calculator applies a 1.2g/kg (0.54g/lb) protein floor regardless of your stated goal. GLP-1 medications cause rapid weight loss, and a meaningful share of that loss can be lean mass rather than fat. Adequate protein is the single biggest lever you have to protect muscle during treatment (Mayo Clinic, 2026).
This floor currently coincides with the fat-loss multiplier, but they come from independent research and are tracked separately so they can diverge as the evidence evolves.
How to Use Your Results
Once you have your goal:
- Track consistently: use Protein Pal to log your daily intake
- Spread it out: distribute protein across 3 to 4 meals for optimal muscle protein synthesis
- Choose quality sources: include a mix of animal and plant proteins
- Adjust as needed: recalculate if your weight or goals change
Common Questions
Q: Should I check the GLP-1 medication box?
Yes, if you're taking semaglutide (Ozempic, Wegovy), tirzepatide (Mounjaro), liraglutide (Saxenda), or other GLP-1 receptor agonists. The calculator will apply a 1.2g/kg (0.54g/lb) lean-mass floor, which overrides whatever goal you've selected.
Q: Can I eat too much protein?
For healthy individuals with normal kidney function, protein intakes well above the muscle-gain target are considered safe in the literature (Antonio et al., 2016, JISSN). Beyond around 1.6g/kg there's little additional benefit for muscle gain.
Q: What about protein timing?
Total daily intake is what matters most. Older guidance suggested an "anabolic window" and a hard 20 to 40g per-meal cap, but more recent work has walked that back. A 2023 study by Trommelen et al. showed muscle protein synthesis continues for many hours after a single 100g dose, meaning the body uses larger meals more efficiently than once thought (Trommelen et al., 2023, Cell Reports Medicine). Hit your daily target consistently and don't stress about exact per-meal distribution.
Ready to Track Your Protein?
Now that you know your target, the next step is tracking your daily intake. The Protein Pal app makes it simple to log your meals, track your progress, and hit your protein goals consistently.