Protein Intake Calculator
This protein calculator finds your daily protein target from your body weight and goal — with an evidence-based range and a per-meal amount.
Most adults need at least 0.8 g/kg of body weight in protein daily, rising to 1.2–2.0 g/kg for active people and 1.6–2.2 g/kg to build or preserve muscle.
How much protein you need
Protein needs scale with your body weight and how active you are, so the standard approach is to multiply your weight in kilograms by a factor in grams per kilogram. The RDA of 0.8 g/kg is a minimum to prevent deficiency in sedentary adults — not an optimal target if you train. Active people generally do better at 1.2–2.0 g/kg, and anyone building or trying to keep muscle usually lands in the 1.6–2.2 g/kg range.
Protein matters most when you're losing weight or building muscle: eating enough protects lean tissue, keeps you fuller, and supports recovery. Once you have a target, split your whole day's calories with the macro calculator, and estimate how many calories you burn with the TDEE calculator.
Getting it right
Aim to spread protein across the day rather than loading one meal — roughly 0.25 g/kg per meal (about 20–40 g), across three to four meals, is a practical guide. Whole-weight targets can overestimate needs if you carry a lot of body fat; in that case base the number on lean mass using the body fat calculator. Treat the result as a range to hit consistently, not a precise daily quota.
Protein targets by goal
| Goal / population | Protein (g/kg/day) | Example at 70 kg |
|---|---|---|
| Sedentary (RDA minimum) | 0.8 | 56 g |
| General health / active | 1.2–1.6 | 84–112 g |
| Endurance training | 1.2–1.4 | 84–98 g |
| Muscle gain | 1.6–2.2 | 112–154 g |
| Fat loss (keep muscle) | 1.6–2.4 | 112–168 g |
| Older adult 65+ | 1.0–1.2 | 70–84 g |
Factors applied to body weight; example grams at 70 kg (154 lb). The muscle-gain range anchors on the ~1.6 g/kg breakpoint from Morton (2018).
Sources: NIH/IOM RDA; ACSM/AND/DC 2016 position stand; ISSN 2017; Morton et al. (2018) meta-analysis; PROT-AGE (Bauer 2013). General information, not medical advice.
Frequently asked questions
How much protein do I need per day?
It depends on your body weight and goal. A common starting point is your weight in kilograms times a factor: about 0.8 g/kg for sedentary adults (the RDA minimum), 1.2–2.0 g/kg for active people, and 1.6–2.2 g/kg if you lift weights and want to build or preserve muscle. In imperial units that muscle-building range is roughly 0.7–1.0 gram per pound. The calculator applies your chosen band to your weight and shows a range plus a recommended midpoint.
Is 1 gram of protein per pound of body weight necessary?
The '1 gram per pound' gym rule equals about 2.2 g/kg, which is the upper end of the evidence-based range for people doing resistance training. Research (Morton 2018 meta-analysis) found muscle-building benefits generally plateau around 1.6 g/kg/day, with a confidence range up to about 2.2 g/kg. So 1 g/lb is a safe, generous target for hard training, but not a strict requirement — most people gain fine at the lower end.
Should I calculate protein from total body weight or lean mass?
The published g/kg guidelines were derived using total body weight, so total weight is the default here. However, for people carrying a lot of body fat, applying g/kg to total weight can overestimate needs — using lean body mass or an adjusted weight is more accurate in that case. If you know your body-fat percentage, base it on lean mass instead.
Do older adults need more protein?
Evidence suggests yes. The PROT-AGE expert group recommends healthy adults over 65 aim for 1.0–1.2 g/kg/day (versus the 0.8 g/kg RDA) to help preserve muscle and function, and 1.2–1.5 g/kg/day for those who are active or managing illness. This is general information, not a substitute for medical advice.
Can eating too much protein be harmful?
For healthy people with normal kidney function, intakes in the ranges shown here are considered safe in the research literature; very high intakes are usually just unnecessary rather than harmful. However, people with kidney or liver disease, other medical conditions, or who are pregnant should follow individualized guidance from a clinician or registered dietitian rather than a general calculator.
Sources
- National Academies — Dietary Reference Intakes: Energy, Carbohydrate, Fiber, Fat, Protein, and Amino Acids (2005) — RDA 0.8 g/kg protein for adults
- Jäger et al. — International Society of Sports Nutrition Position Stand: Protein and Exercise (2017) — 1.4-2.0 g/kg; 20-40 g per meal
- Thomas, Erdman & Burke — Nutrition and Athletic Performance (Academy/DoC/ACSM joint position, 2016) — Athlete protein needs 1.2-2.0 g/kg
- Bauer et al. — PROT-AGE Study Group: Optimal Protein Intake in Older People (2013) — Older adults 1.0-1.2 g/kg protein
The thresholds and formulas used by this calculator follow the primary sources above. This tool provides general information, not personalised medical advice.