Calorie Calculator
Start from your TDEE, choose a goal — lose fat, maintain, or build muscle — pick how fast you want to move, and get a daily calorie target that respects hard calorie floors, with an optional zigzag plan of higher and lower days that averages to the same number.
Your details
Every useful calorie target begins from one number: how much you burn. This calculator takes your total daily energy expenditure (estimated with the same transparent Mifflin–St Jeor plus activity-factor pipeline as our TDEE calculator) and turns it into a goal-specific daily target. Three goals, four paces, one arithmetic chain you can inspect at every step — no black box, no promised outcomes.
The goals are simple to state. Cut: eat below your TDEE, at a pace of 0.25 to 1.0 kg of body-weight change per week, using the conventional 7,700 kcal per kilogram conversion. Maintain: eat at your TDEE. Bulk: eat above it — and because muscle gain is slow, the surplus is deliberately half the cut rate (a 0.5 kg/week bulk adds roughly half the calorie increment a 0.5 kg/week cut removes), so the surplus stays modest by construction.
Two honesty features are built in, because a calorie target without guardrails is how people end up at 900 kcal/day wondering why they feel awful. First, calorie floors: we will not display a target below 1,500 kcal/day for men or 1,200 kcal/day for women. If your chosen pace would go under the floor, you get the floor value plus an explicit message telling you the pace is too aggressive for your stats, and pointing you toward professional guidance. Second, the adaptation note: a static target is an initial estimate, not a promise — as your weight changes and your body adapts, the right number moves with it, which is why we frame every projection as a starting point to recalibrate, not a guaranteed outcome (Hall KD, et al. Lancet. 2011;378(9793):826-837).
TDEE base: Mifflin–St Jeor resting estimate × activity factor (1.2–1.9 ladder; rough mapping, not a validated standard), identical to the TDEE calculator pipeline.
Cut: TDEE − (pace × 7,700 ÷ 7). Maintain: TDEE. Bulk: TDEE + (pace × 7,700 ÷ 7 × 0.5), paces 0.25 / 0.5 / 0.75 / 1.0 kg per week.
Floors: men ≥ 1,500 kcal/day, women ≥ 1,200 kcal/day. A target below the floor is clamped to the floor and announced, never silently changed.
Zigzag: optional +250 / −250 alternating days; weekly average unchanged. Display rounds to 10 kcal; conversions use 1 kcal = 4.1868 kJ.
How the goal wizard turns your TDEE into a target
The chain is transparent arithmetic on top of the estimate from our TDEE calculator (Mifflin–St Jeor resting estimate × activity factor). From that TDEE: a cut subtracts pace × 7,700 ÷ 7 kcal per day; maintenance adds zero; a bulk adds pace × 7,700 ÷ 7 × 0.5. The half-multiplier on bulking reflects the physics of tissue gain — muscle is built slowly, so a surplus sized like a cut surplus mostly buys fat.
Worked example: with a TDEE of 2,000 kcal/day, cutting at 0.5 kg/week subtracts 7,700 × 0.5 ÷ 7 ≈ 550, giving a target of 1,450 kcal/day — which, for a woman, sits below the floor (next section), so the wizard would return the floor with a warning instead. The same TDEE with a 0.25 kg/week pace gives about 1,725 kcal/day, comfortably above it. All values round to the nearest 10 kcal at display; the weekly total, the high and low zigzag days, the kilojoule conversion, and the projected weekly change are each shown as independent fields so you can sanity-check the arithmetic yourself.
Calorie floors: when we refuse to go lower
Very-low-calorie diets are a medical intervention with supervision requirements, not a DIY setting — so this calculator enforces floors of 1,500 kcal/day for men and 1,200 kcal/day for women, a conservative boundary in line with common clinical practice. If your chosen goal and pace would push the target below the floor, three things happen: you get the floor value, clearly labelled as the floor; you get an explicit message that your pace is too aggressive for your stats and that a slower pace or professional guidance is the right next step; and the projected weekly change is shown at the floor, not at the fantasy number.
The floor is not a judgement about willpower — it is the point where the arithmetic of "faster is better" stops being true and starts being counterproductive: very large deficits erode training quality, lean mass, and adherence, and adaptation shrinks the deficit's effect anyway. If you are considering going below the floor deliberately, or the calculator keeps warning you at modest paces, that is a conversation for a qualified professional, not a settings change. This tool never silently raises or lowers your target — constraint conflicts are always announced.
Zigzag high and low days without changing your average
Some people find a flat daily target hard to live with — weekends, training days, and social meals don't distribute evenly across the week. The optional zigzag plan keeps your weekly average identical while varying the days: high days add 250 kcal, low days subtract 250 kcal, so a 2,000 kcal target becomes 2,250 and 1,750 in alternation. Over any even stretch of days the average is unchanged, which is the only property that matters for the underlying estimate.
A few honest caveats. The ±250 band is a product convenience within the commonly used ±200–300 range, not a validated protocol — there is no solid evidence that zigzag timing meaningfully outperforms a flat target for weight change. What it genuinely helps with is adherence, which is the quiet variable that decides most real-world outcomes. If you use it, put the high days on your hardest training days and count the average, not any single day, as your scoreboard.
Why progress slows: the adaptation note
A static target describes the first weeks of a phase honestly and later weeks less so. As weight falls on a cut, your body needs less energy to move and maintain itself; in addition, sustained deficit triggers adaptive changes — less fidgeting, slightly lower resting expenditure — that shrink the effective deficit below what the spreadsheet says. Dynamic weight models built on measured data quantify exactly this drift (Hall KD, et al. Lancet. 2011;378(9793):826-837. DOI:10.1016/S0140-6736(11)60812-X), which is why the projections on this page are labelled initial estimates and why the honest response to a stall is recalibration, not a crash cut.
The practical loop: pick your target here, eat at it consistently for two to three weeks, compare your average weekly weight trend against the projection, and adjust by 100–200 kcal based on reality rather than re-deriving theory. If you are stuck between adjustments, the calorie deficit calculator reframes the same math from the deficit side, and the macro calculator splits your chosen target into protein, carbohydrate, and fat.
Frequently asked questions
How many calories should I eat to lose weight?
Fewer than you burn — how many fewer is the pace question. At the standard 0.5 kg/week pace, the deficit is about 550 kcal/day below your TDEE; at a gentle 0.25 kg/week, about 275. This calculator computes it from your stats and enforces floors of 1,500 kcal/day (men) and 1,200 (women): if your stats and pace collide with the floor, you get the floor plus an explicit warning rather than a number that looks precise but is unsafe. Slower paces also preserve training quality and lean mass better, and are easier to hold.
Is a calorie target from a calculator something I can trust long-term?
As a starting point, yes; as a permanent fixture, no. It rests on an activity estimate that is admittedly rough, a 7,700-kcal-per-kg conversion that is an average rather than a law, and a body that adapts to sustained deficits. The right mental model is "initial target, then calibrate": two to three weeks of consistent eating and scale data tell you more than any equation. When reality and the target disagree, adjust the target.
Why does this calculator refuse to go below 1,200 or 1,500 calories?
Because below that range you are in very-low-calorie-diet territory, which clinically is a supervised intervention, not a self-serve setting. The floors are conservative boundaries, not optima — most people do better on more food and more patience. If the floor keeps triggering for you, the correct moves are a slower pace or professional guidance, and the calculator says so explicitly rather than quietly bending your inputs.
What is zigzag dieting and is it better than a flat target?
Zigzagging alternates higher and lower days — here, +250 and −250 around your average — so the weekly total is unchanged. There is no solid evidence it outperforms a flat target for weight change; what it can help with is adherence, by letting harder training days or social meals carry more of the budget. Treat it as a scheduling preference, not a physiological trick, and judge yourself on the weekly average.
How big should my surplus be for muscle gain?
Smaller than most people set it. Muscle protein synthesis is slow, so energy beyond what synthesis can use is stored as fat. That is why this calculator halves the bulk increment relative to a cut at the same pace (a 0.5 kg/week bulk adds roughly 275 kcal/day, not 550). Combined with adequate protein and progressive resistance training — the macro calculator handles the protein side — a modest surplus captures nearly all of the muscle-building benefit with far less fat to remove later.
My weight stalled even though I'm hitting my target. Now what?
First, check the trend, not single weigh-ins: water, sodium, and digestion swing day to day by more than real fat change. If the two-to-three-week average is truly flat, the usual suspects are a creeping activity drop, underestimated portions, or plain adaptation — your current body is smaller and thriftier than the one the target was computed for. Adjust by 100–200 kcal and repeat the loop. Persistent stalls at already-low intakes are another case where professional input beats calculator iteration.
References & sources
Mifflin MD, St Jeor ST, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990;51(2):241-247. DOI:10.1093/ajcn/51.2.241.
Supports: The resting-energy equation that anchors the TDEE your calorie target is built on.
Does not support: Does not validate the activity ladder, the 7,700 kcal/kg conversion, or any goal-specific target derived here.
Frankenfield D, Roth-Yousey L, Compher C. Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults: a systematic review. J Am Diet Assoc. 2005;105(5):775-789. DOI:10.1016/j.jada.2005.02.005.
Supports: The basis for using Mifflin–St Jeor as the default resting estimate for healthy adults, and for framing results as estimates rather than measurements.
Does not support: Does not provide individual error guarantees or cover athletes, older adults, or clinical populations.
Hall KD, Sacks G, Chandramohan D, et al. Quantification of the effect of energy imbalance on bodyweight. Lancet. 2011;378(9793):826-837. DOI:10.1016/S0140-6736(11)60812-X.
Supports: Why fixed-deficit projections drift over time and why this page labels every target an initial estimate to be recalibrated.
Does not support: This calculator does not implement the full dynamic model from that work; the citation explains the limitation rather than endorsing our arithmetic.