By Zencalcy Editorial TeamLast reviewed About us
This calculator estimates daily protein from your body weight and activity level, then divides the total across three meals. Protein targets are usually expressed in grams per kilogram of body weight because the number scales with body size. The result is a planning anchor for a normal eating pattern, not a medical prescription.
Daily protein grams from body weight and activity.
Protein (g/day) = weight(kg) × (base g/kg + goal adjustment) Protein per meal = daily total ÷ 3
Base multipliers are 0.8 g/kg for sedentary adults, 1.2 g/kg for active people, 1.6 g/kg for athletes and 2.0 g/kg for strength-focused training. Fat loss and muscle gain add 0.2 g/kg; fat loss uses the extra protein to help preserve lean mass in an energy deficit.
| Symbol | Meaning |
|---|---|
| weight | Body weight in kilograms. |
| base g/kg | Protein multiplier for the selected activity level. |
| goal adjustment | 0 g/kg for maintenance, +0.2 g/kg for loss or gain. |
| per meal | Daily protein divided by three meals. |
An 80 kg person at the active multiplier of 1.2 g/kg with no goal adjustment needs 80 × 1.2 = 96 g of protein per day. Spread over three meals that is 32 g per meal. Choosing fat loss instead would raise the target to 1.4 g/kg, or 112 g per day.
Protein is usually prescribed in grams per kilogram because body weight is simple to measure and the resulting target scales with body size. The multipliers here sit inside ranges commonly cited for sedentary adults, active people and strength athletes. Two caveats matter. First, at a high body-fat percentage, using total weight can overshoot because fat mass needs little protein, so some clinicians anchor the calculation to lean mass instead. Second, distribution across meals may influence muscle protein synthesis, which is why the tool divides the daily total into three portions. Treat the number as a planning anchor, then adjust based on hunger, training load, recovery and progress over several weeks.
Continue with the BMR Calculator (Mifflin-St Jeor), Harris-Benedict Calculator, or the Katch-McArdle Calculator — or browse more dietary tools and all health calculators.
Also see the Calorie Calculator, TDEE Calculator and the Macro Calculator.
The result depends on body weight and activity. Sedentary adults are commonly cited at 0.8 g/kg, active people around 1.2 g/kg and strength athletes up to about 2.0 g/kg. This tool uses those multipliers and adds 0.2 g/kg for fat loss or muscle gain.
Energy and nutrient estimates are population guidance, not personal prescriptions. Actual needs vary with body composition, medical conditions, medication, pregnancy and activity. Values are rounded and should be discussed with a registered dietitian or clinician when used to plan treatment.
Reference material used to build and check this calculator:
Last reviewed: September 2026. See how we build and check every tool on the about page.
Content updated: September 2026