Most Fitness Tools
LIE TO YOU.
We only built tools where the science was already settled. Every calculator here is backed by peer-reviewed research — not bro-science, not gym myths. Just what actually works.
498+ subjects validated our calorie formula
We show you which study we used — and why
If better research exists, we update the tool
5 tools available · More coming soon
Maintenance Calories
Mifflin-St Jeor · 1990
Body Fat %
Navy Method · HODGDON 1984
Protein Intake
Morton et al. · 2018
TDEE Calculator
Activity-adjusted · Multi-study
THE TOOLKIT
Built on Research. Designed for Results.
TDEE Calculator
Total daily energy with activity
Breathable Fat Loss Calculator
84% fat exhaled as CO₂ · BMJ 2014 · Live ticker · Instagram card
Sleep-Impact Fat Loss Calculator
Sarcopenia Risk Meter · UChicago 2010 · Ghrelin/Leptin Hormones
New tools are added as we validate the underlying research. No guesswork. Ever.