Enter six numbers and get what you need to maintain your weight, plus working targets for losing fat or building muscle. The math runs on the Mifflin-St Jeor equation, the formula with the best accuracy record when you don't know your body fat percentage. You don't need to hand over an email to see your numbers.
calories per day to maintain your current weight
Your BMI: 25.8 (overweight range)
Treat these numbers as starting points. If a medical condition or medication affects your weight or appetite, get your targets from your doctor or a registered dietitian.
A calorie calculator estimates your maintenance calories, meaning the energy your body burns in a typical day and therefore the intake at which your weight holds steady. Eat under that number consistently and you lose weight. Eat over it and you gain. Every diet that has ever worked, worked through that mechanism.
The estimate has two parts. Your basal metabolic rate covers what your body burns just staying alive, which for most people is the large majority of the total. An activity multiplier then scales it up for training, walking, and everything else you do in a day. If you want the full breakdown of where those calories go, that's total daily energy expenditure, and the TDEE calculator walks through each component.
What this page gives you is the practical output. One maintenance number, and what to eat relative to it for your goal.
This calculator uses the Mifflin-St Jeor equation, published in 1990 and still the best-validated formula for people who don't know their body fat percentage. In a major review by the American Dietetic Association, it predicted measured metabolic rates more reliably than the older Harris-Benedict formula.
Your BMR then gets multiplied by an activity factor, from 1.2 if you sit most of the day up to 1.9 if you train ten or more hours a week.
Two honest caveats. The activity multipliers were built decades ago and tend to run high for people with desk jobs who train a few hours a week; if you're unsure, pick the lower of two options. And any formula is a population average, so treat your result as a starting point with roughly a ten percent margin either way. Two weeks of scale data tells you more than any equation.
To lose fat. Use the steady-cut band, which sits about 20 percent under maintenance. That's the deficit research keeps landing on as the workable middle: fast enough to see the scale move, moderate enough that training and energy hold up. Expect to lose around 0.5 to 1 percent of your body weight per week. Keep protein high while you cut, and recalculate after every ten pounds or so, because a lighter body burns fewer calories.
To maintain. Eat at the maintenance number and judge it by the two-week average on the scale instead of any single morning weigh-in. Day-to-day weight swings with water, salt, and sleep; the trend line is the signal.
To build muscle. Use the lean-gain band, about 5 to 10 percent over maintenance. The scale should climb slowly. If it's jumping, you're gaining faster than muscle can be built and the difference is fat. A structured lifting plan matters more than the surplus itself; that's what the training guides are for.
A calculator hands you a target in thirty seconds. The hard part is hitting it through work trips, family dinners, and the weeks training falls apart. That gap is what 1:1 coaching covers. You get custom programming, nutrition guidance, and weekly check-ins tailored to your schedule, your equipment, and your goals, with progress review, form feedback, and program adjustments every single week. Programs written by a registered nurse who trains around full clinical shifts, not a full-time fitness guy.