Health & Fitness
Biological markers and nutritional audits for a quantified life.
TDEE is your "Maintenance Level"—the total fuel your body burns in a day.
What time do you plan to close your eyes?
Understanding BMI
Body Mass Index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, overweight and obesity in adults. While it doesn't measure body fat directly, it is a reliable indicator of healthy weight for most people.
Metabolism & TDEE
Your Total Daily Energy Expenditure (TDEE) is an estimation of how many calories you burn per day when exercise is taken into account. It is calculated by first figuring out your Basal Metabolic Rate (BMR), then multiplying that value by an activity multiplier.
Blood Alcohol Estimation
The Widmark Formula is used to approximate Blood Alcohol Content (BAC) based on the amount of alcohol consumed and the person's weight and sex. Metabolism usually removes alcohol at a rate of roughly 0.015% per hour. Never drive after consuming alcohol based on an online calculator. Legal limits and biological reactions vary significantly.
The Sleep Cycle Optimizer
Waking up in the middle of a sleep cycle often results in "sleep inertia"—that groggy feeling even after long rest. Human sleep cycles typically last about 90 minutes. This calculator finds the optimal times to wake up by counting 90-minute blocks from your bedtime, ensuring you wake up at the end of a cycle.
Naegele's Due Date Rule
Standard due date estimation adds one year, subtracts three months, and adds seven days to the first day of your last menstrual period (LMP). While biologically only about 5% of babies are born on their actual due date, this provides the clinical baseline for the 40-week gestation period.
Hydration Science
Every cell and organ in your body needs water to function correctly. Factors like body weight and exercise intensity significantly impact your daily requirements. A general rule is 35ml per kg of body weight, plus compensatory fluids for exercise.
Training Zones
Heart Rate Zones define the intensity of your cardiovascular training. Zone 2 is the 'fat-burning' zone, ideal for building aerobic base, while Zone 4 is your lactic threshold, essential for increasing top-end speed and performance.
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