About
Nutrition math, shown in full
Calorie Calculator exists because of a small, stubborn annoyance: every calorie calculator on the internet uses the same handful of published equations — and almost none of them will show you the arithmetic. You get a number, an email-capture form, and a wall of ads. We thought the number deserved better manners.
So we built the calculator we wanted to use: instant, free, no account, no ads — and radically transparent. Every result on this site prints its working like a well-typeset lab report: the equation used, your values substituted in, every intermediate step visible. If you disagree with our answer, you can check it with a pencil. That's the point.
What we build on
Nothing here is our invention, and that's deliberate. Our calculations use the Mifflin-St Jeor equation (the formula rated most accurate for healthy adults in the Academy of Nutrition and Dietetics' comparative review), the revised Harris-Benedict equation, and Katch-McArdle for people who know their lean mass. Activity multipliers, deficit sizes, and protein ranges follow the mainstream of published sports-nutrition research.
Where the evidence is genuinely uncertain — and in nutrition it often is — we say so on the page rather than manufacturing false precision. Every estimate is labeled an estimate, and every tool tells you how to calibrate it against the only data that outranks any formula: your own two-week scale trend.
Who is behind Calorie Calculator
Calorie Calculator is built by a small independent team of engineers and nutrition writers, with our long-form guides reviewed against primary sources before publishing. We are not a medical service and don't pretend to be one: nothing on this site is medical advice, and people with medical conditions, a history of disordered eating, or pregnancies should get their numbers from a clinician, not a website.
The project is sustained deliberately without ads or data resale — no tracking pixels stitching your diet questions to an ad profile. We'd rather stay small and be the calculator people trust and link to.
Write to us
Found an error — in the math, the writing, or a translation? Tell us and we'll fix it, credited if you like. We read everything sent through the contact page, and corrections get priority over compliments (though compliments are also accepted).