About FitFixLife

FitFixLife is a free wellness platform built to give you instant, science-backed fitness numbers — no sign-up, no paywalls, no friction.

Why We Built This

Most calorie and fitness calculators on the web are locked behind email gates, cluttered with ads, or give you a single number with no context. We wanted to build something better: a set of connected tools that are fast, accurate, and explain what the numbers actually mean for you.

Science-Backed Formulas

Every tool on FitFixLife uses peer-reviewed formulas trusted by professionals. Our calorie calculator defaults to the Mifflin-St Jeor equation and upgrades to Katch-McArdle when lean mass is known. Our BMI tool follows WHO classification guidelines. Our one-rep max estimator averages seven proven strength formulas for the most reliable result.

Connected Tools

Your results flow from one tool to the next. Calculate your daily calories, then your calorie target feeds into the macro calculator, which feeds into the protein calculator. Enter your data once and build a complete wellness picture.

Ranges, Not Prescriptions

We always show practical ranges and plain-language explanations — never clinical prescriptions. Your numbers are estimates based on well-studied formulas, but individual needs vary. We encourage everyone to consult a healthcare professional for personalized guidance.