Free tools

Calorie deficit calculator

Work out roughly what you burn in a day, and a moderate starting point below it. Nothing you type leaves your device.

Your height
Your weight

Roughly what you burn

1,918 kcal a day

A starting point to try

1,679 kcal a day

This is a starting point to try, not a prescription and not a target you have to hit.

These are estimates from a published equation, not measurements. Two people the same size can burn noticeably different amounts, so take this as somewhere to start and adjust from what actually happens.

If you have ever had a problem with eating, if you are pregnant, or if you are under medical care for your weight, please do not use a calculator for this. Speak to your GP, who can look at the whole picture rather than three numbers.

What a calorie deficit actually is

It is eating a bit less than your body uses. That is the whole idea, and everything else on this page is about how big a bit, and how to work out roughly what your body uses in the first place.

The maintenance figure here comes from the Mifflin-St Jeor equation, which estimates what you burn at rest from your height, weight, age and sex, then multiplies it by an activity factor. It is an estimate. Two people of the same size and age can burn noticeably different amounts, so the number is a starting point rather than a fact about you.

Why this page only offers a moderate deficit

A bigger cut is not a shortcut. Eating far below what you burn tends to cost you sleep, training quality, mood and muscle, and the most common thing that happens next is that it stops. A cut you barely notice is one you can keep going with, and keeping going is the whole game.

So this calculator offers a gentle option and a moderate one and nothing steeper. There is no box to type your own number into, deliberately. It also refuses to display a figure below a floor taken from NHS guidance, and tells you when it has done that rather than quietly rounding you up.

Why the same number does not suit everyone

The equation knows four things about you and there are a great many more that matter: how much muscle you carry, what you do all day beyond deliberate exercise, what medication you take, how you sleep, and what your history with food has been. None of that is in the box.

Common questions

Is a bigger calorie deficit faster?
On paper, and that is not the question worth asking. A steeper cut costs you sleep, training quality and muscle, and it is far more likely to be abandoned. That is why this page does not offer one, and why there is no box to type your own number into.
Why will the calculator not show me a lower number?
Because there is a floor built into it, taken from NHS figures, and no combination of inputs gets underneath it. If your numbers would have produced something lower, the page says so on screen rather than quietly showing you the floor as though it were your result.
How accurate is a calorie calculator?
It is an estimate from a published equation, and individual variation around it is wide. Take the figure as somewhere to start, give it a while, and adjust from what actually happens rather than from what the calculator said.
Why does it ask for my sex?
Because the equation it uses is parameterised on it and there is no neutral version. If you would rather not say, the page shows you both calculations side by side instead of picking one for you.
Should I eat back the calories I burn exercising?
The activity factor in this calculator already includes your training, so you do not need to add exercise on top. Adding it twice is one of the commonest reasons a figure from a calculator comes out higher than it should.

One number, worked out once.

A calculator gives you a figure based on today and then stops. Trael adjusts your intake guidance as your training and your check-ins change, and it will tell you when eating more is the right call rather than only ever pointing one way. See what is included.

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Where the numbers come from

Related

Trael provides general fitness guidance only and is not a substitute for professional medical advice. Always consult a doctor before starting any exercise or diet programme.