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Protein Calculator

Estimate your daily protein needs from your weight and activity, with grams per day and per meal.

Results

ItemValue

Protein by activity

Activityg/kg per dayGrams per day
This is general information for healthy adults, not medical advice. Needs can differ during pregnancy, breastfeeding, older age and illness. If you have kidney disease or another health condition, speak to a doctor or dietitian first.

Quick Answer

The US recommended intake for healthy adults is 0.8 g of protein per kilogram of body weight a day. A person weighing 180 lb (81.6 kg) would need about 65 g a day. People who train regularly may need more, and sports guidance for athletes is about 1.2 to 2.0 g per kilogram.

Last updated: 2 November 2026 ·How we calculate this: US protein RDA and sports nutrition ranges

Table of Contents

How This Protein Calculator Works

Protein needs are usually based on body weight. This calculator converts your weight to kilograms and multiplies it by a range for your activity. It shows your daily total, a per-meal amount, and how each activity level compares.

Quick explanation: protein (g) = body weight (kg) × grams per kilogram.

  • General adult: 0.8 g/kg, the US RDA.
  • Endurance training: about 1.2 to 1.4 g/kg.
  • Strength training: about 1.6 to 2.0 g/kg.

How to Use the Protein Calculator

  1. Enter your body weight and choose pounds or kilograms.
  2. Pick the activity level that fits you best.
  3. Enter how many meals you eat a day.
  4. Press Calculate to see your daily protein and a per-meal amount.
  5. Compare activity levels in the second table if your training changes.

Core Formulas

  • Weight in kg: pounds × 0.45359237
  • Daily protein: weight in kg × g/kg target
  • Per meal: daily protein ÷ meals

The RDA is the amount needed to prevent deficiency in most healthy adults. It is a minimum guide, not an ideal target for everyone. Sports nutrition sources recommend 1.2 to 2.0 g/kg for athletes, depending on training.

Worked Example

You weigh 70 kg and do endurance training.

  • Low end = 70 × 1.2 = 84 g a day
  • High end = 70 × 1.4 = 98 g a day
  • Over 3 meals = about 28 to 33 g a meal

Real-Life Examples

  • A 150 lb office worker: at the 0.8 g/kg RDA, that is about 54 g a day, or roughly 18 g per meal over 3 meals.
  • A 200 lb lifter: at 1.6 to 2.0 g/kg, that is about 145 to 181 g a day. Over 4 meals, that is about 36 to 45 g per meal.
  • A 60 kg marathon runner: at 1.2 to 1.4 g/kg, about 72 to 84 g a day.
  • Plant-based eating: the same targets apply. Beans, lentils, tofu, soy milk and nuts can help you reach them.

Protein per Kilogram vs Percentage of Calories

  • Grams per kilogram: ties protein to your body size. This calculator uses this method.
  • Percentage of calories: US guidelines give 10-35% of calories from protein. Our Macro Calculator uses this method.
  • Why they differ: a percentage changes when your calories change, even if your body weight does not.
  • Use both: check that your grams per kilogram also fit inside the 10-35% range.

Daily Protein by Body Weight

Grams of protein per day, rounded.

Body weightGeneral (0.8 g/kg)Endurance (1.2-1.4)Strength (1.6-2.0)
120 lb (54 kg)44 g65 – 76 g87 – 109 g
140 lb (64 kg)51 g76 – 89 g102 – 127 g
160 lb (73 kg)58 g87 – 102 g116 – 145 g
180 lb (82 kg)65 g98 – 114 g131 – 163 g
200 lb (91 kg)73 g109 – 127 g145 – 181 g
220 lb (100 kg)80 g120 – 140 g160 – 200 g
250 lb (113 kg)91 g136 – 159 g181 – 227 g

What Can Change Your Needs

  • Training: more or harder training can raise your needs.
  • Calories: protein needs can be higher when eating fewer calories.
  • Age: older adults may have different needs.
  • Health: kidney disease and other conditions may change what is safe for you.

Common Mistakes to Avoid

  • Using pounds as kilograms. Multiply pounds by 0.4536 first, or choose pounds above.
  • Treating the RDA as a goal for athletes. It is a minimum for most healthy adults.
  • Eating it all in one meal. Spreading protein across meals is easier for many people.
  • Forgetting calories. Protein foods still add calories to your day.
  • Ignoring health conditions. People with kidney disease need medical advice before eating more protein.

Frequently Asked Questions

The US RDA is 0.8 g per kilogram of body weight for healthy adults. Enter your weight above for your own number.

Sports nutrition guidance for strength training is often about 1.6 to 2.0 g per kilogram a day, along with resistance training.

Multiply pounds by 0.4536 to get kilograms, then multiply by your g/kg target.

Healthy people usually handle higher intakes, but people with kidney disease should get medical advice before raising protein.

Many people find it easier to spread protein through the day. The per-meal figure gives you a simple target.

Some research suggests older adults may benefit from more than 0.8 g/kg. Ask a doctor or dietitian what suits you.

No. Most people can meet their needs with food. Powder is simply a convenient option.

If you have a lot of weight to lose, many dietitians base protein on a goal or adjusted weight. Ask a professional if you are unsure.

References & Sources

SourceUsed ForLink
NIH Office of Dietary Supplements, Exercise and Athletic Performance Athlete protein range of 1.2 to 2.0 g/kg. https://ods.od.nih.gov/factsheets/ExerciseAndAthleticPerformance-HealthProfessional/
Phillips SM et al., Optimizing Protein Intake in Adults (PMC) The protein RDA and how to apply it. https://pmc.ncbi.nlm.nih.gov/articles/PMC5347101/
The effect of protein intake on athletic performance (PMC) Typical endurance and strength ranges. https://pmc.ncbi.nlm.nih.gov/articles/PMC11613885/
ISSN Position Stand: protein and exercise Protein intake for exercising people. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5477153/