Protein Calculator

What this protein calculator does

Protein supports muscle, organs, enzymes, and immune function. This calculator estimates daily protein ranges from body weight and calorie intake using three common references: the American Dietetic Association, the CDC, and the World Health Organization.

The result is a range, not a prescription. Needs vary with age, activity, pregnancy, illness, and kidney health.

How to use this calculator

1. Enter age, sex, height, and weight.
2. Choose a BMR formula and activity level.
3. Click Calculate to see the three reference ranges.

The default example is a 25-year-old man who is 5 ft 10 in and weighs 160 lb with a light activity level.

Protein formulas

ADA range = 1.0 to 1.8 g per kg of body weight
CDC range = 10% to 35% of daily calories ÷ 4
WHO safe lower limit = 0.8 g per kg

What the results mean

• ADA: a broad range for generally healthy adults.
• CDC: a calorie-based range; the upper end is high for most people.
• WHO: a minimum intake to prevent deficiency in healthy adults.

For the default example, the ADA range is about 73–131 g/day, the CDC range about 59–207 g/day, and the WHO lower limit about 58 g/day.

Assumptions and limitations

The calculator uses body weight and calorie estimates. It does not account for pregnancy, lactation, older age, illness, surgery, or kidney disease. Athletes and people doing resistance training may need more than the WHO minimum.

People with kidney disease should not increase protein without medical advice. Food source and amino acid quality also matter.

Frequently asked questions

How much protein do I need to build muscle?

Many active adults aim for about 1.2–2.0 g/kg/day, spread across meals. The optimal amount depends on training, energy intake, and goals.

Is more protein always better?

No. Very high intake can be unnecessary and may be harmful for people with certain medical conditions. Balance protein with other nutrient-dense foods.

Does this include plant protein?

The calculation is for total protein. Plant and animal sources can both contribute; the amino acid profile and overall diet matter.

Should older adults eat more protein?

Some guidance suggests higher intake for older adults to support muscle mass, but individual needs vary. Discuss it with a clinician or dietitian.

Source

References:

• Dietary Guidelines for Americans
• NIDDK — Body Weight Planner

Disclaimer

This calculator is for informational and educational purposes only. It is not medical advice. Consult a registered dietitian or clinician for individual protein recommendations.