Protein Intake Calculator

Why protein is measured per kilo, not per calorie

Most macro calculators start from calories and give protein a percentage — 30% of 2,200 calories, say. That works fine when calories are high, and quietly fails when they aren't.

Drop to 1,500 calories to cut, keep the 30% split, and protein falls to 112 g. For a 90 kg person that's 1.2 g/kg — below what the evidence supports during a deficit, precisely when holding onto muscle matters most. Protein needs track body weight and training load, not total intake. That's why this page asks for weight and goal, and never for calories.

Six scenarios, six numbers

The bottom row is the one people find surprising: the target goes up when you eat less, not down. In a deficit, protein is doing two jobs — providing the raw material for repair and protecting lean mass from being burned for energy.

Worked example

Default profile: 165 lb (74.8 kg), strength training.

74.8 kg × 1.6 g/kg = 119.7 → 120 g per day
74.8 kg × 1.4 g/kg = 104.8 → 105 g (range low)
74.8 kg × 2.0 g/kg = 149.7 → 150 g (range high)
120 g × 4 kcal/g   = 480 kcal
480 ÷ 2,000        = 24% of a 2,000-calorie day

What 120 g looks like in food

No single row is a plan — 6.7 cups of lentils is not a day anyone enjoys. The point of the table is scale: hitting 120 g means a protein source at every meal plus one deliberate snack. A realistic day looks like eggs at breakfast, chicken at lunch, Greek yogurt as a snack, and fish or tofu at dinner.

At 150 g (the cutting target for the same person) those become 4.3 servings of chicken, 6.8 cups of yogurt, 6 scoops of whey, or 8.3 cups of lentils.

Splitting across meals

Distribution matters less than the daily total, but it isn't irrelevant:

• 3 meals — 40 g each. Fine if you eat substantial meals.
• 4 meals — 30 g each. The most common recommendation, and the easiest to hit without planning.
• 5 meals — 24 g each. Useful if large portions sit badly, or if you're eating in a deficit and want volume.

The often-quoted "30 g maximum per meal" comes from studies of muscle protein synthesis in young men at rest. More recent work puts the practical ceiling higher — around 0.4 g/kg per meal, which is 30 g at 75 kg and 40 g at 100 kg — and total daily intake still dominates. Don't reorganise your life around it; do spread protein across the day rather than eating 100 g at dinner.

If you think in pounds

The rule of thumb worth memorising: 0.7 g per pound for training, 0.9 g per pound while cutting.

Three things this calculator won't tell you

Plant protein isn't one-to-one. Most plant sources are lower in leucine and less digestible, so the practical target is often 10–20% higher — around 1.8–2.0 g/kg for a plant-based lifter rather than 1.6. Soy and pea isolates narrow the gap considerably.

"Protein" on a label isn't all absorbed. The digestibility-corrected score (DIAAS) for whole foods ranges from about 0.5 for some grains to over 1.0 for dairy and eggs. This calculator doesn't adjust for it.

More is not better indefinitely. Intakes up to about 2.2 g/kg are well supported for training. Beyond that, the extra mostly gets oxidised. There's no evidence of harm in healthy kidneys, but there's also no additional benefit.

How to use this calculator

1. Pick US or metric units and enter your body weight.
2. Choose the scenario that matches your training, not your aspiration.
3. Read the daily grams and the range around them.
4. Use the per-meal row that matches how often you actually eat.
5. Scroll to the food table to sanity-check what the number means.
6. Compare with the RDA row to see how far above the minimum you are.

Frequently asked questions

How much protein do I need a day?

For training adults, 1.4–2.0 g per kg of body weight — 105–150 g for someone at 165 lb. The adult RDA of 0.8 g/kg (60 g at the same weight) is a minimum to avoid deficiency, not a target for people who train.

How much protein per meal?

Around 0.4 g per kg of body weight, which is 30 g at 75 kg. In practice, 25–40 g per meal across three or four meals covers it. Daily total matters more than the exact split.

Is 150 g of protein too much?

Not for a 165 lb person — that's 2.0 g/kg, inside the supported range and a reasonable target while cutting. It becomes excessive relative to evidence somewhere above 2.2 g/kg, and it's a lot of food volume for someone eating 1,500 calories.

Can I get 120 g of protein without supplements?

Yes, comfortably. Three eggs (19 g), a chicken breast (35 g), a cup of Greek yogurt (22 g), and a portion of fish or tofu at dinner (30 g) gets you past 100 g before snacks. Supplements are convenient, not necessary.

Does protein timing matter?

The "anabolic window" is much wider than the gym-bro version suggests — total daily intake and even distribution matter more than eating within 30 minutes of training. A protein-containing meal within a couple of hours either side of a session is enough.

Do I need more protein as I get older?

Yes. Ageing blunts the muscle protein synthesis response to a given dose, so older adults are commonly advised to aim for the higher end of the range — around 1.2–1.6 g/kg — and to include 25–30 g of good-quality protein per meal.

Data sources: The 0.8 g/kg adult RDA follows the Institute of Medicine Dietary Reference Intakes (2005). Training ranges follow the International Society of Sports Nutrition position stand on protein and exercise (Jäger et al., 2017), which supports 1.4–2.0 g/kg for resistance training and higher intakes during energy restriction; the 2.2 g/kg ceiling reflects the upper end of that literature. Per-meal guidance of roughly 0.4 g/kg draws on dose-response work on muscle protein synthesis. Food values are typical composition figures for common servings and vary with brand, cut, and cooking method — chicken breast at 4 oz cooked ≈ 35 g, plain nonfat Greek yogurt at 1 cup ≈ 22 g, whey at one scoop ≈ 25 g, cooked lentils at 1 cup ≈ 18 g. All figures are reproducible from the default inputs (165 lb, strength training).

Disclaimer: This calculator is a general estimate for reference and is not medical or nutritional advice. Protein needs change with medical conditions — particularly kidney disease, where higher intakes may need supervision — and with pregnancy and lactation. If any of those apply, talk to a clinician or registered dietitian before changing your intake. Related tools: macro calculator, calorie calculator, calorie calculator for muscle gain, TDEE calculator, all health calculators.