TDEE Calculator for Weight Loss

Take your maintenance level, your TDEE, and subtract the deficit that matches the rate you want. Roughly 550 calories a day, or 2,300 kilojoules, gives about half a kilogram a week; roughly 1,100 calories a day gives about one kilogram. The calculator above does this from your own height, weight, age, sex and activity level rather than a generic figure, and it will not take you below your BMR.

The average adult reference on Australian food labels is 8,700 kJ a day for maintenance, not for weight loss. For loss, work out your own maintenance and subtract about 2,300 kJ a day for half a kilogram a week, or about 4,600 kJ a day for one kilogram. Most Australian adults land somewhere between 6,000 and 9,000 kJ a day when losing weight, which is why the calculator gives you a figure rather than a rule of thumb.

Deficit equals maintenance minus what you eat. To turn a deficit into a rate, divide by 7,700, the approximate calories in a kilogram of body tissue: a 500 calorie daily deficit is 3,500 a week, or about 0.45 kg. That arithmetic is a straight line and your body is not, so expect the real rate to lag the calculated one, particularly after the first month.

At 0.5 kg a week, about 20 weeks. At 0.75 kg a week, about 14 weeks. At 1 kg a week, about 10 weeks, though that rate is hard to hold and only realistic if your maintenance is high enough to leave a deficit that large above your BMR. Enter a goal weight in the calculator and it gives you the weeks and a date based on your own numbers rather than the averages.

BMR is what you would burn lying still all day. TDEE is BMR multiplied by an activity factor, so it includes moving, working, training and digesting. TDEE is the number that matters for weight loss, because it is your maintenance level, and BMR matters because it sets the floor a sensible target should not go under.

No calculator measures your metabolism. Every one of them, this included, applies a population equation to your height, weight, age and sex, and those equations are accurate to within roughly 10 per cent for most people and further out for some. Measured resting metabolic rate testing is the accurate version, and it needs equipment. The practical answer is to pick a starting figure, hold it for three or four weeks, and let your own weight trend correct it.

This page shows two equations rather than one, Schofield and Mifflin St Jeor, so you can see the spread instead of trusting a single figure.

For many adults, yes. Around 1,200 calories, roughly 5,000 kJ, is the commonly quoted lower bound for women and 1,500 calories, roughly 6,300 kJ, for men, and plenty of people have a BMR above those figures, which means eating at them puts you below your resting requirement. Intakes that low also make it hard to reach iron, calcium, B12 and omega-3 targets from food. This calculator will not display a target below that floor or below your own BMR, and it tells you when the rate you picked has been capped.

The usual candidates are that maintenance has fallen as you have got lighter, that intake has drifted upward without it feeling that way, or that water and cycle changes are hiding a real loss on the scale. If it has been several weeks on a genuinely steady intake and nothing has moved, it is worth looking at thyroid function, iron stores and sleep before cutting further, because eating less is not the answer to every stall.

Yes. Sex at birth changes the equation used, because average body composition differs, so male and female estimates diverge even at identical height and weight. The calculator is built for adults aged 18 and over. It is not suitable during pregnancy or breastfeeding, or for anyone with a history of disordered eating, and it is not designed for children or teenagers.