⚖️ The judge shows their work.
Most calorie apps hand you a number and expect you to trust it. This page explains exactly how yours is built, which formulas we use, and where those formulas come from, so you can judge them for yourself.
Your BMR
The energy you burn doing nothing at all
Your Basal Metabolic Rate is what your body spends just staying alive: breathing, circulating blood, keeping warm. We calculate it with the Mifflin–St Jeor equation, using your weight, height, age, and biological sex.
A 2005 systematic review by the Academy of Nutrition and Dietetics compared the common prediction equations and found Mifflin–St Jeor the most accurate for most people, which is why dietitians tend to reach for it first.
Your TDEE
What you actually burn in a day
Total Daily Energy Expenditure is your BMR multiplied by how much you move. These multipliers are the long-established activity factors used alongside BMR equations.
In Full Manual mode we do something stricter: we start you at the sedentary floor (1.2) and let your budget grow only when you log real activity. Nothing is assumed on your behalf.
Your daily budget
How the goal changes what you can eat
To lose weight you eat below your TDEE. About 7,700 kcal is stored in roughly one kilogram of body fat, so a target of 0.5 kg a week works out to about 550 kcal a day below your burn.
We cap the fastest pace at 1 kg a week. Health bodies including the CDC, the NHS, and the Mayo Clinic all point to about 0.5 to 1 kg (1 to 2 lb) a week as the sustainable range, and faster is usually water and muscle rather than fat.
Your budget is also never allowed below a safe floor: 1,500 kcal for men and 1,200 kcal for women. If your chosen pace would push you under that, we hold the floor and tell you to move more instead of eating less.
Your macro rings
Protein first, then the rest
Protein is set first, as a floor based on your body weight: 1.6 g/kg to maintain, 1.8 g/kg while losing (a deficit needs more protein to protect muscle), and 2.2 g/kg if you turn on Build Muscle. That range comes from the International Society of Sports Nutrition position stand and a large 2018 meta-analysis by Morton and colleagues.
Whatever calories remain after protein are split between carbs and fats according to your diet preference. Standard uses a 55/45 split, which sits inside the Acceptable Macronutrient Distribution Ranges set by the Institute of Medicine. Keto instead caps carbs and gives fat the rest.
Doing it in that order is deliberate. It means your three rings always add back up to your calorie budget, instead of quietly asking you to eat more (or less) than you are allowed.
Where this comes from
Named findings only — go read them yourself.
Mifflin MD, St Jeor ST, et al. (1990)
A new predictive equation for resting energy expenditure in healthy individuals. The equation behind your BMR.
Frankenfield D, Roth-Yousey L, Compher C (2005)
Systematic review for the Academy of Nutrition and Dietetics comparing prediction equations. Mifflin–St Jeor came out most accurate.
Jäger R, Kerksick CM, et al. (2017)
International Society of Sports Nutrition position stand on protein and exercise. Basis for the protein targets.
Morton RW, Murphy KT, et al. (2018)
Meta-analysis of protein supplementation and resistance training, supporting protein intakes around 1.6 g/kg and above.
Institute of Medicine (2005)
Dietary Reference Intakes, including the Acceptable Macronutrient Distribution Ranges used for the carb and fat split.
CDC, NHS, and Mayo Clinic guidance
Public health advice on losing about 0.5 to 1 kg (1 to 2 lb) a week, which sets our fastest pace.
What these numbers cannot do
They are estimates, not measurements
Prediction equations are built from population averages and typically land within about 10 percent of the truth for most people. Two people with identical stats can genuinely burn different amounts. Only lab testing measures your real rate.
Weight loss is not perfectly linear
The 7,700 kcal per kilogram rule is the standard teaching tool, but your metabolism adapts as you lose weight, so real progress usually runs a little slower than straight-line math predicts. Treat the weekly pace as a direction, not a promise.
Your best data is the scale over time
Use these targets as a starting point, then adjust. If your weight is not moving the way you expect after two or three consistent weeks, your real burn is probably a little different from the estimate.
🩺 Not medical advice
My Calorie Judge is a general wellness and tracking tool. It is not a medical device, and nothing here is a diagnosis, treatment, or personalised clinical advice.
Talk to a doctor or a registered dietitian before changing how you eat if you are pregnant or breastfeeding, under 18, managing diabetes, heart, kidney, or thyroid conditions, taking medication affected by diet, or have any history of disordered eating. If something here conflicts with what your clinician tells you, follow your clinician.