About FitCalculation

What this is

FitCalculation is a set of eleven fitness calculators: TDEE, calorie targets, macro splits, protein, BMI, body fat, and the goal calculators that combine them. They are free, they need no account, and they run entirely in your browser.

The site exists because most calculators make you take the number on faith. You are handed 2,480 kcal/day and given no way to find out where it came from, how wrong it might be, or which equation was used. Here, all three are on the table — the methodology page names every formula, links to the paper behind it, and states the error and the limitations for each one.

Who runs it

FitCalculation is an independent project built by a software developer. It is not affiliated with any medical body, university, or commercial supplement brand, and it does not sell anything.

Who has reviewed it

Nobody, medically. There is no physician or registered dietitian reviewing these tools, and this site will not pretend otherwise by displaying a credential it does not have.

What has been done is the part that can actually be verified: the equations are published, the sources are cited, the constants live in one place in the code rather than being scattered and adjusted, and the calculators' limits are stated rather than hidden. Arithmetic is checkable in a way that clinical judgement is not — anyone can open the methodology page, follow the citations, and confirm the maths.

If this site's approach to you seems thin, it is. The honest version of the claim is "we show our work", and we would rather make that clear than borrow authority we have not earned.

What these calculators are not

• Not medical advice. Nothing here diagnoses, treats, or replaces consultation with a professional.
• Not a nutrition plan. A calorie target is a number. What you eat, whether you can sustain it, and whether it suits you are separate questions these tools cannot answer.
• Not precise. Every figure here is an estimate from population-level equations, and most have error bars worth several percent. The methodology page says which is which.
• Not suitable for everyone. Anyone pregnant or breastfeeding, under 18, managing diabetes, kidney disease, an eating disorder history, or any other clinical condition should not set calorie or protein targets from a general calculator. Ask a professional instead.

How it is funded

It is not, currently. No accounts, no paywall, no affiliate links, no tracking of the numbers you enter. If that changes, it will be disclosed on this page rather than buried — a calculator that quietly sells your data while claiming to help you would be a contradiction.

Corrections

Formulas get revised and code gets refactored. If a number here looks wrong, tell us and it gets looked at. The editorial policy describes how, and how quickly.