About HealthCalc

What HealthCalc is

HealthCalc is a small, independently run website with seven calculators: BMI, basal metabolic rate, body fat percentage, heart rate zones, water intake, running pace, and daily calorie needs with a food database behind it. Each one does a single calculation and then explains what the number means.

The site exists for a simple reason: most calculator sites give you a number and nothing else. You cannot tell whether the formula is reputable, whether it applies to you, or what it leaves out. HealthCalc puts the formula, the source, and the limitations on the same page as the result.

What it is for

You might be checking a number you were given elsewhere, tracking a trend over several weeks, or trying to work out whether a question is worth taking to a doctor. HealthCalc is useful for those three things. It is not a substitute for care.

It is also useful for anyone curious about where these numbers come from. Every formula is cited to a public source you can go and read.

Who runs it

HealthCalc is run independently by a software developer. There is no company behind it, no sales team, and no medical institution. Nobody involved in running the site is a doctor, and no part of this site has been reviewed or approved by a clinician.

That is a deliberate choice, not a gap to be filled with borrowed authority. Inventing a medical advisory board to look more credible would tell you less than a plain statement of who wrote the code and which sources the formulas came from.

How the numbers are chosen

Formulas are taken from public health bodies, national health services, and the published dataset behind each calculator. Where calculators disagree, the one traceable to a named authority wins. Where an estimate is genuinely contested, the calculator says so rather than picking a side silently.

Some things are deliberately absent. We have not built a TDEE calculator, because the activity multipliers used for daily expenditure are not well enough established to present as a confident number. The reasoning is written up in the Source and Methodology page.

How it is funded

HealthCalc may carry advertising. Advertising never influences a formula, a source, a category boundary, or the advice given on any page. We do not accept payment to change a result, and we do not sell or share anything you type into a calculator.

If advertising is what makes it possible to keep the site running, that is worth knowing when you weigh it. The calculators themselves are free, and none of them is paywalled.

Corrections

If a formula is wrong, a citation is dead, or a translation is inaccurate, we want to know. The contact page has the details. Mistakes in health information get fixed.