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Protein calculator

If you are training and want to hold onto muscle, the useful range is roughly 1.6 to 2.2 grams of protein per kilogram of body weight per day. The official RDA of 0.8 g/kg is a different thing entirely: the amount that prevents deficiency in a sedentary adult, not the amount that supports a body you are trying to change.

Written by the Calybite team · Last updated 25 August 2026

Your protein target

104–143 g

Per day. The adult RDA floor is 52 g — a minimum to avoid deficiency, not a target for body composition.

BMR (at rest)

1,370 kcal

TDEE (maintenance)

2,123 kcal

BMI (context only)

23.8 · Healthy weight

Estimates for generally healthy adults, using Mifflin-St Jeor. Real expenditure varies by roughly ±10% between people of identical size. Not medical advice — if you have a medical condition, are pregnant, or are recovering from an eating disorder, talk to a professional before using a calorie target.

Protein is the macro people miss. Calybite shows the running total as you log.

Log a meal in four seconds and see it against your numbers.

Point the camera at the plate. Calybite names it, counts it, and holds it against the target above.

Two numbers that get confused

Almost every argument about protein comes from treating one number as though it were the other:

RDA           0.8 g/kg   prevents deficiency in sedentary adults
Active range  1.6–2.2 g/kg   supports lean mass when training
                             or in a calorie deficit

For a 154 lb (70 kg) person that is 56 grams versus 112 to 154 grams — a difference of nearly three times. The RDA is a public-health floor set to keep a population out of deficiency. It was never intended as a performance target, and reading it as one is why “you only need 56 grams” and “you need 150 grams” can both be cited from official sources without either side being wrong.

Where the upper end stops mattering

The meta-analytic evidence points to benefits flattening out somewhere around 1.6 g/kg for muscle gain in most trained people, with a plausible ceiling near 2.2. Above that, extra protein is not harmful for healthy kidneys — it simply stops buying anything, and it starts crowding out the carbohydrate and fat you would rather eat.

The one case for pushing toward the top of the range is an aggressive calorie deficit. The leaner you get and the steeper the deficit, the more protein does to protect muscle — which is the difference between losing weight and losing the tissue you wanted to keep.

Spread it out, roughly. Three or four servings of 25 to 40 grams across the day is the usual recommendation, and it is easier to hit than one enormous dinner. That said, total daily intake matters considerably more than timing — do not let perfect distribution stop you eating the total.

Which weight to use

The calculator uses your current body weight, which is the right default for most people. If you carry a lot of excess fat, the guidance scales better against lean body mass or a target weight — fat tissue does not need feeding with protein, and using total weight can produce an unnecessarily large number. In that situation, calculating against your goal weight is a reasonable adjustment.

Hitting it is the hard bit

Protein is the macro people most consistently miss, and usually not by a little. Estimating it by eye is difficult because it is concentrated in a few foods and nearly absent from many others, so a day can look balanced on the plate and land forty grams short.

This is where component-level recognition earns its keep: identifying that a plate held chicken thigh rather than “curry” changes the protein figure substantially. Calybite, the AI food-tracking app, names each component and matches it against verified nutrition entries, then shows you the result to confirm before it saves.

Related: split your calories into macros to see protein alongside fat and carbohydrate, or size your calorie deficit — the two interact more than either does alone.

Sources

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Back to all calculators.

Stop doing the arithmetic.

A calculator gives you the target once. Calybite holds every meal against it — no credit card, no payment gateway, and free meal scans every day.

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