Protein Intake Calculator
Estimate your daily protein target in grams from body weight and goal.
Results update as you type.
About this calculator
A protein intake calculator recommends daily protein based on your body weight and goal, expressed in grams per kilogram of body weight. The RDA floor is about 0.8 g/kg, while active people and those building muscle need more — commonly 1.6–2.2 g/kg. It shows a sensible range plus a single midpoint target.
The calculation multiplies your body weight by the g/kg range for your goal and takes the midpoint as your target. For a 70 kg person on the build-muscle setting (1.6–2.2 g/kg) that is a range of about 112–154 g and a target near 133 g per day. Split across four meals, the per-meal figure is roughly 33 g — close to the 0.3–0.4 g/kg per sitting that best stimulates muscle protein synthesis.
Enter your weight in kilograms or pounds and choose the goal that matches your activity, from sedentary maintenance up to fat loss while keeping muscle. Higher targets suit strength training and dieting, where extra protein preserves lean mass and keeps you full. This is general nutrition guidance for healthy adults, not medical advice.
Frequently asked questions
How much protein do I need per day?
It scales with body weight and activity: about 0.8 g/kg for sedentary adults, 1.2–1.6 g/kg for general fitness, and 1.6–2.2 g/kg when building or preserving muscle. This protein intake calculator multiplies your weight by that range.
Should protein be based on total or lean body weight?
For most people total body weight works well and is what these g/kg ranges assume. If you carry a lot of excess fat, basing the target on lean body mass or goal weight avoids over-estimating your needs.
Does protein timing matter?
Total daily protein matters most. Spreading it across roughly four meals of 0.3–0.4 g/kg each helps muscle protein synthesis, which is why the per-meal figure is shown.
How much protein do I need to build muscle?
For muscle gain the tool uses 1.6–2.2 g/kg. A 70 kg lifter lands around 112–154 g a day, with a midpoint near 133 g. Research shows little added benefit from going much above about 2.2 g/kg.
How much protein should I eat per meal?
The calculator divides your daily target by your number of meals, four by default. Roughly 0.3–0.4 g/kg per meal — about 20–40 g for most people — maximises the muscle-building response at each sitting.
Can too much protein be harmful?
For healthy people, intakes up to about 2 g/kg are well tolerated. Those with kidney disease should follow their clinician’s advice, since protein needs are managed differently — this tool is general guidance, not medical advice.
Do I enter my weight in pounds or kilograms?
Either. Switch the units selector to imperial and the tool converts pounds to kilograms internally, because the g/kg ranges are defined per kilogram of body weight.
API — use this calculator from code
Call this calculator as a free JSON endpoint — no key required. Send the field values below as query parameters or JSON. Read the full API docs →
Endpoint
GET https://calculator.free/api/v1/protein-intake/curl
curl "https://calculator.free/api/v1/protein-intake/?units=metric&weight=70&goal=1.6-2.2"JavaScript fetch()
const r = await fetch(
"https://calculator.free/api/v1/protein-intake/?" + new URLSearchParams({
"units": "metric",
"weight": "70",
"goal": "1.6-2.2"
}));
const data = await r.json();
console.log(data.results);Results are estimates for general guidance only, not financial, medical or tax advice.