Free Health & Fitness Calculators
Simple, private health and fitness calculators — work out your BMI and healthy weight range, find your heart rate training zones, and time your sleep cycles. Educational tools, not medical advice.
Sleep Cycle Calculator
Calculate the ideal bedtime or wake-up time based on 90-minute sleep cycles. Wake up refreshed, not groggy.
- Health
- Sleep
- Calculator
BMI & Healthy Weight Calculator
Calculate your Body Mass Index, healthy weight range, and category. Supports metric and imperial units.
- Health
- Fitness
- Calculator
Heart Rate Zone Calculator
Calculate your 5 heart rate training zones using the Karvonen formula. Enter age and resting heart rate.
- Health
- Fitness
- Training
Related Guides
Frequently Asked Questions
Are these health calculators free?
Yes — all health and fitness calculators are free, with no signup required.
Is this medical advice?
No. These are educational tools and are not a substitute for advice from a healthcare professional.
Is my data private?
Yes. Calculations run in your browser; nothing you enter is sent to a server.
Which units are supported?
The BMI calculator supports both metric and imperial units; the others work from age, heart rate, or time inputs.
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