Protein Calculator
Calculate your optimal daily protein intake based on body weight, goal, and activity level. Evidence-based targets from the Morton et al. 2018 meta-analysis. Free.
All calculations run instantly in your browser. No data is sent to any server.
Disclaimer: Results are for informational purposes only and do not constitute medical advice, diagnosis, or treatment. Consult a qualified healthcare professional for personal guidance.
Protein Recommendations by Goal
| Goal | g/kg/day | Source |
|---|---|---|
| Sedentary adult | 0.75 | UK RNI |
| Active / sport | 1.2–1.6 | ACSM / ISSN |
| Muscle gain | 1.6–2.2 | Morton et al. 2018 |
| Cutting (preserve muscle) | 2.2–3.1 | Helms et al. 2014 |
| Older adult (55+) | 1.2–1.6 | Bauer et al. 2013 |
Protein Quality
Not all protein sources are equal. Leucine content and digestibility determine how well a protein source stimulates muscle protein synthesis. Animal sources (chicken, fish, eggs, dairy) have high leucine content and excellent digestibility. Plant sources can be combined to achieve complete amino acid profiles — combining rice + pea protein achieves a profile comparable to whey. Soy protein is the highest-quality complete plant protein source.
FAQs
How much protein per day?
Sedentary: 0.75 g/kg (UK RNI). Resistance training / muscle gain: 1.6–2.2 g/kg — maximised at 1.62 g/kg per Morton et al. meta-analysis (2018). Cutting: up to 3.1 g/kg to preserve muscle.
Does protein timing matter?
Distribute 20–40g across 3–4 meals every 3–4 hours (Areta et al., 2013). Post-workout window helpful but not critical if total daily intake is adequate.