The Problem with Existing Calculators
Most online calorie calculators are cluttered, slow, and filled with ads. They often use outdated formulas or don't give you enough detail to understand your results. We wanted to fix that.
We believe accurate calorie calculation should be simple, fast, and accessible to everyone. Our goal is a BMR and TDEE calculator that shows its work and keeps your inputs on your own device.
Most online calorie calculators are cluttered, slow, and filled with ads. They often use outdated formulas or don't give you enough detail to understand your results. We wanted to fix that.
Calorie Professor combines accuracy, speed, and design. We use the most current scientific formulas (Mifflin-St Jeor as the default), show all calculations transparently, and make it beautiful to use.
Your calculator inputs never leave your device — all calculations run in your browser. We don't sell your data or show you ads, and the only analytics we run is aggregate Google Analytics traffic measurement.
Compare Mifflin-St Jeor, Harris-Benedict, and Katch-McArdle. See which formula works best for you.
Go beyond calories. Get daily protein, carb, and fat targets for cutting, maintaining, or building muscle, with protein scaled up in a deficit to protect lean mass.
Get a 14-day zigzag diet schedule to help prevent metabolic adaptation and keep results consistent.
Built with Vercel's Geist design system. Fast, minimal, and beautiful. No clutter, no ads.
Optimized for performance. All calculations happen instantly in your browser with zero lag.
See exactly how your results are calculated. No black boxes, no proprietary algorithms.
Optional 7-day meal plans tailored to your gender, diet type, and allergen restrictions.
Use the calculator in English, Spanish, French, German, Portuguese, Chinese, Japanese, Hindi, Arabic, Russian, Korean, Italian, or Dutch.
Switch between light and dark themes for comfortable viewing day or night. Your preference is saved automatically.
Developed in 1990 and validated in numerous studies, Mifflin-St Jeor is considered the most accurate formula for calculating BMR in people with normal body composition.
For men: (10 × weight_kg) + (6.25 × height_cm) - (5 × age) + 5
For women: (10 × weight_kg) + (6.25 × height_cm) - (5 × age) - 161
This formula accounts for age, gender, weight, and height, making it reliable for most populations.
TDEE is calculated by multiplying your BMR by an activity factor that ranges from 1.2 (sedentary) to 1.975 (extra active). We use the widely-accepted Harris-Benedict activity multipliers.
Sedentary: 1.2
Lightly active: 1.375
Moderately active: 1.55
Very active: 1.725
Intensely active: 1.9
Extra active: 1.975
Every formula on this site is named and displayed as an equation, so you can check the arithmetic yourself. The primary references behind the calculator are:
Activity multipliers follow the widely used Harris-Benedict classifications. Protein targets during a deficit are set high enough to help protect lean mass, in line with recommendations for athletes in an energy deficit (Helms et al., above).
Calorie Professor is built with Astro for performance, TypeScript for reliability, and Vercel's Geist design system for its visual language. We aim to follow WCAG 2.1 AA guidance: a single logical heading order, labelled form controls, keyboard-operable menus, visible focus states, and sufficient color contrast in both light and dark themes.
The interface is available in 13 languages, including right-to-left layout for Arabic. Language and theme preferences are stored locally in your browser and persist across visits.
The calculator is maintained and updated as feedback and new research come in. Additions so far include the Katch-McArdle option, the calorie-cycling schedule, dark mode, expanded language coverage, and the optional meal plan generator.
If you spot an error, have a suggestion, or want to help improve a translation,get in touch.
Start using Calorie Professor today and discover your daily calorie needs with precision.
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