Health Guide exists to make evidence-based health tools accessible to everyone — for free, with no account required, and with complete respect for your privacy. Every number our calculators produce comes from the same population-based equations used in clinical research and public health guidelines.
Our 11 calculators use established equations — Mifflin-St Jeor for BMR/TDEE, the U.S. Navy method for body fat, Devine and Robinson formulas for ideal weight, and Karvonen for heart rate zones. These are the same reference formulas used in dietitian offices and sports medicine clinics.
Any health data you enter — age, weight, height, activity level — stays in your browser's localStorage. It is never sent to our servers, never stored in a database, and never shared with third parties. You can delete it at any time by clearing your browser data.
Our Health Planner is not a generic checklist. It runs all 11 calculators silently against your profile, assigns each result an urgency score from 0–100, and surfaces the top action in each health pillar — Move, Eat, and Live. You see only the three things that matter most for you today.
| Calculator | Formula / Method |
|---|---|
| BMI | WHO standard: weight (kg) ÷ height² (m²) |
| BMR | Mifflin-St Jeor (1990) |
| TDEE | BMR × Harris-Benedict activity multiplier |
| Body Fat % | U.S. Navy circumference method |
| Ideal Weight | Devine (1974), Robinson (1983), Miller (1983) |
| Calories Burned | MET values (Ainsworth et al., Compendium of Physical Activities) |
| Macro Split | AMDR ranges (Institute of Medicine dietary reference intakes) |
| Heart Rate Zones | Karvonen heart rate reserve method |
| Waist-to-Height Ratio | WHO boundary values (0.5 threshold) |
| Water Intake | EFSA and U.S. National Academies AI values |
| Pregnancy Due Date | Naegele's rule (LMP + 280 days) |
All results from Health Guide are estimates based on population averages. They are not medical advice and do not account for individual health conditions, medications, or clinical history. Always consult a qualified healthcare provider before making changes to your diet, exercise, or health routine. See our full Medical Disclaimer.