Informational tools
Health Calculators & Utilities
Three calculators for U.S. readers with assumptions shown in plain language.
Metabolic Biomarker Index
Enter any values from a recent lab report to see where each sits against commonly cited U.S. cut-points, plus two ratios drawn from research literature.
- Units. Glucose, triglycerides, and HDL in mg/dL. A1C in percent.
- What is calculated. The TyG index, ln(triglycerides x glucose / 2), and the triglyceride-to-HDL ratio.
- What it is not. It is not a clinically validated index or an established medical test.
- Reference ranges. Interpret lab results using the ranges printed on your own lab report and your clinical context.
Circadian Sleep Window Estimator
Pick the time you need to wake up and how much sleep you prefer. The tool works backward to a bedtime window, including when that time falls before midnight.
- Method. Wake-up time, minus sleep duration, minus the time you usually take to fall asleep.
- Individual variation. Sleep needs and body-clock timing differ between people.
- Limits. It cannot diagnose a sleep disorder or promise better sleep.
Hydration Planner
Enter your weight, activity, and environment for a daily fluid-planning range. The assumptions are listed with every result.
- Baseline. 30 to 35 mL of fluid per kilogram of body weight, with additions for activity and heat.
- Context. The National Academies list about 3.7 L (men) and 2.7 L (women) of total water per day from all drinks and foods as an adequate intake. This planner is a simpler estimate.
Fluid restrictions. If your clinician has advised you to limit fluids, for example because of heart, kidney, or liver conditions, follow their instructions and do not use this planner. The result is not a prescription.
Bring your numbers to an appointment
Estimates are most useful as conversation starters. A few notes make them more useful to a clinician.
- Write down the date of each lab test and whether you fasted.
- List your medications and supplements, including doses.
- Note sleep, activity, and hydration habits in plain terms.
- Prepare two or three questions about what matters most to you.