What is FitUtils?

FitUtils is a free collection of health and fitness calculators built for people who want accurate, no-nonsense tools. There's no account required, no subscription, and no data sent to any server. Everything runs directly in your browser.

Our goal is simple: give you the information you need to understand your body — backed by science, presented clearly, and available to anyone with a browser.

We built FitUtils because most health calculators online require signups, use outdated formulas, or are clunky to use and uninformative. FitUtils is lean, fast, and honest about what these numbers mean.

Our Mission

Health information should be accessible to everyone. We believe that understanding your body — from your BMI to your daily calorie needs — shouldn't require a gym membership, a nutritionist appointment, or a subscription to a wellness app.

Data Sources

All FitUtils calculators use formulas and reference data from peer-reviewed research and globally recognized health organizations:

WHO

World Health Organization — BMI classification standards and global health guidelines.

NCD-RisC

NCD Risk Factor Collaboration — global BMI distribution data used for percentile estimates.

CDC

U.S. Centers for Disease Control and Prevention — additional reference data for adult BMI and weight categories.

Mifflin-St Jeor

The gold-standard equation for Basal Metabolic Rate (BMR), used in our upcoming BMR/TDEE calculators.

Privacy Commitment

We take privacy seriously. All calculations happen in your browser — your height, weight, and other inputs are never sent to our servers. We use IP geolocation (via ipapi.co) only to set your default unit system (Imperial for US users, Metric for everyone else), and this data is not stored or logged by us.

Read our full Privacy Policy.

Our Calculators

  • BMI Calculator — Body Mass Index, category, healthy weight range, and how close you are to an ideal BMI.
  • TDEE Calculator — Coming soon
  • BMR Calculator — Coming soon
  • 1RM Calculator — Coming soon

Contact

Questions, feedback, or spotted an error in our formulas? Reach us at gwalkmanvova@gmail.com. We read every message.