Compare calculators
Both calculators run independently β change the inputs on either side to compare results.
Health
Sleep Cycle & Wake Time Calculator
Work backward from your desired wake time to find the ideal bedtime based on your age and sleep quality factors. Use this to wake up at the end of a sleep cycle feeling naturally refreshed.
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 β 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
| Sleep Cycle & Wake Time Calculator | Body Fat Calculator (Navy Method) | |
|---|---|---|
| Category | Health | Health |
| Inputs required | 4 | 5 |
| Result | Optimal Bedtime (hours before midnight) | Estimated Body Fat (%) |
| What it does | Work backward from your desired wake time to find the ideal bedtime based on your age and sleep quality factors. Use this to wake up at the end of a sleep cycle feeling naturally refreshed. | Estimates body fat percentage using the U.S. Navy circumference method, which needs only a tape measure β 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. |