About Calorie Deficit Calculator

A free, transparent, frontend-only tool for estimating your daily calorie needs and projected weight loss.

Our Mission

We built the Calorie Deficit Calculator to provide accurate, science-based estimates without any hidden costs, sign-ups, or data collection. All calculations run entirely in your browser using the Mifflin-St Jeor equation and standard activity multipliers.

Why We Built This

Many online calculators are cluttered with ads, trackers, and unclear assumptions. We wanted to create a clean, user-friendly tool that shows exactly how your results are calculated. Every formula and multiplier is documented on our Methodology page.

What Makes Us Different

100% frontend – no server, no API, no tracking. Your inputs never leave your device.
Transparent formulas – we display every step of the calculation.
Evidence-based – uses the Mifflin-St Jeor equation recommended by health organizations.
Honest estimates – we clearly label projections as estimates, not guarantees.
Accessible & responsive – designed for all devices and screen readers.

Important Disclaimer

This calculator is for educational purposes only and does not replace professional medical advice. Always consult a qualified healthcare provider before making significant changes to your diet or exercise routine.