Compare calculators
Both calculators run independently — change the inputs on either side to compare results.
Health
Heart Rate Training Zones Calculator
Finds your target heart rate for each training zone using either the simple percentage-of-max method or the more precise Karvonen formula. Use it to structure cardio workouts for fat burning, aerobic base, or peak performance.
Fill in the required fields to see your result.
Health
Body Fat Calculator (Navy Method)
Estimates body fat percentage using the U.S. Navy circumference method, which needs only a tape measure — no calipers or scales. It combines neck, waist, height (and hip for women) into a validated equation used by the military for body-composition screening.
Fill in the required fields to see your result.
Key differences
| Heart Rate Training Zones Calculator | Body Fat Calculator (Navy Method) | |
|---|---|---|
| Category | Health | Health |
| Inputs required | 4 | 5 |
| Result | Target Heart Rate (bpm) | Estimated Body Fat (%) |
| What it does | Finds your target heart rate for each training zone using either the simple percentage-of-max method or the more precise Karvonen formula. Use it to structure cardio workouts for fat burning, aerobic base, or peak performance. | Estimates body fat percentage using the U.S. Navy circumference method, which needs only a tape measure — no calipers or scales. It combines neck, waist, height (and hip for women) into a validated equation used by the military for body-composition screening. |