The CalorieGap

Three things separate this from a standard calorie calculator, and all three exist because the standard approach is known to overestimate.

Daily movement and exercise are counted separately

Almost every calculator uses one blended “activity level” slider running from about 1.2 to 1.9. Those multipliers come from a long tradition rather than strong evidence, and they routinely overshoot, which is why so many people find their calculator number doesn’t work. Two people with the same desk job who both lift four times a week can differ by several hundred calories a day on step count alone, and one slider can’t see that. So your baseline comes from how much you move in ordinary life, and your training is added on top of it.

Exercise is counted net, not gross

A workout doesn’t burn its full listed calorie count on top of your day: you would have burned something in that hour anyway, just sitting there. Adding the gross figure double-counts your resting metabolism. This tool subtracts it, which is why the exercise contribution here looks smaller than the number on a treadmill display.

Deficits and surpluses are percentages, not flat numbers

The familiar “cut 500 calories” rule ignores body size: it’s a punishing deficit for a small person and barely registers for a large one. Adjustments here are a share of your own maintenance, sized to a sensible rate of change: roughly half a percent of body weight a week for steady fat loss, up to about one percent at the faster setting. Beyond that pace, more of what you lose is muscle rather than fat, and the leaner you already are the worse that trade gets.

Where the macros come from

Protein is set first, using the same engine as The Protein Gap: a range keyed to your goal, your training, and your age, calculated on a reference weight rather than scale weight. Fat is set next with a floor of about 0.5 g per kilogram, because fat is needed for hormone production and to absorb fat-soluble vitamins: that floor is never breached to make the other numbers work. Carbohydrate is the remainder. It’s fuel, not a moral category, and it’s the macro that most affects how your training sessions feel.

Fiber follows the Dietary Reference Intake of 14 grams per 1,000 calories, calculated on your maintenance level rather than your goal level so that cutting calories doesn’t quietly cut your fiber target too.

What this tool can’t do

Predictive equations land within about 10% for a group and scatter considerably wider for individuals. Nobody can tell you your metabolic rate from four measurements: not this tool and not any other. That’s why the number here is a starting point paired with a way to check it, and why the two-week protocol matters more than the estimate does.

The “pounds per week” projection uses the familiar 3,500-calories-per-pound approximation. It holds up reasonably for the first few weeks and drifts afterwards, as a smaller body burns less and adaptation sets in. Treat it as a direction, not a schedule.

Calorie targets here are floored at your estimated resting metabolic rate, and never fall below 1,200 (women) or 1,500 (men) regardless of what the arithmetic says.

Needs are different during pregnancy and breastfeeding, and this tool doesn’t cover them. Neither does it cover children or teenagers. Nothing here is medical advice or a diagnosis.