A walkthrough, end to end.
- 1
Enter your body weight and select a goal that matches your activity.
- 2
The calculator multiplies weight (kg) by an evidence-based g/kg target.
- 3
See per-meal targets — most research shows ~0.4 g/kg per meal across 3–5 meals maximizes muscle protein synthesis.
Protein targets
RDA is 0.8 g/kg — the minimum to prevent deficiency, not the optimum. Research from ISSN, ACSM, and meta-analyses (Morton 2018, Stokes 2018) supports 1.6–2.2 g/kg for active people pursuing muscle gain. Cutting at a deficit warrants higher (~2.0–2.4 g/kg) to preserve lean mass.
What you can do with this.
Protein for muscle gain
1.6–2.2 g/kg/day. Above ~2.2 g/kg shows diminishing returns in well-controlled studies. Distribute across 3–5 meals of 0.3–0.4 g/kg each for optimal MPS.
Protein on a cut
2.0–2.4 g/kg/day during a calorie deficit. Higher protein preserves lean mass and improves satiety — both critical when calories are restricted.
Protein for endurance athletes
1.2–1.6 g/kg/day. Endurance training increases needs above sedentary baseline but less than strength training. Marathoners doing 2-a-days lean toward 1.6.
Protein for older adults (50+)
Targets shift up to 1.2–1.6 g/kg/day even without training, to offset age-related sarcopenia. Strength training amplifies the muscle-preserving effect significantly above this baseline.
Protein for vegetarians and vegans
Plant proteins are typically lower in leucine. Add ~10% to your target (so 1.8–2.4 g/kg for muscle gain) and combine sources — soy + grains + legumes covers full essential amino-acid profiles.
Protein for weight loss
Higher protein during a deficit reduces hunger and preserves muscle. Studies show 25–30% of calories from protein outperforms 15% on body-composition outcomes at the same calorie target.
Protein for women
Women's needs are equivalent on a g/kg basis — there's no biological case for lower targets. Many fall short because portion sizes track lower; aim for 25–35 g per meal across 3–4 meals.
Protein timing around workouts
The post-workout 'anabolic window' is much wider than the gym-bro 30-minute claim — current research supports 4–6 hours. As long as a 0.3–0.4 g/kg meal happens within that window, MPS is maximized.
Protein calculator 2026 — what's current
ISSN 2017 and updated 2024 reviews continue to support 1.6–2.2 g/kg for trained populations. New evidence: leucine threshold (2.5–3 g/meal) matters more than total grams for older adults.
Frequently asked.
For healthy people, no clinically significant harm up to ~3.0 g/kg. Old kidney concerns have been debunked in healthy individuals; existing kidney disease is the exception.
Animal proteins are typically higher in leucine and have more complete amino acid profiles. Plant-based eaters can match by combining sources (e.g., legumes + grains) and aiming slightly higher total.
0.3–0.4 g/kg per meal (so ~25–35 g for a 75 kg person), every 3–5 hours. More than ~0.55 g/kg in one sitting plateaus MPS.
No — whole foods (chicken, eggs, fish, dairy, tofu, lentils) are more nutrient-dense. Powder is a convenience tool, not a requirement. Use it when meeting your target with food alone is impractical.
Children typically meet needs through normal eating. Active teens benefit from 1.2–1.6 g/kg, especially during growth spurts. This calculator is built for adults — discuss specific child targets with a pediatric dietitian.
No. Calculations run entirely in your browser — no server processing, no analytics on inputs, no cookies.