Glossary
Definitions, formulas, and worked examples for the concepts behind our free calculators — health, productivity, and money.
Health
- Body Mass Index (BMI) Body Mass Index (BMI) is a screening ratio that compares body weight to height squared, expressed as…
- Basal Metabolic Rate (BMR) Basal Metabolic Rate (BMR) is the estimated number of calories your body expends at complete rest to…
- Total Daily Energy Expenditure (TDEE) Total Daily Energy Expenditure (TDEE) is the estimated sum of all calories you burn in twenty-four hours,…
- Body Fat Percentage Body fat percentage is the proportion of total body mass that is adipose tissue, contrasting with lean mass…
- Waist-to-Height Ratio (WHtR) Waist-to-height ratio (WHtR) is a simple anthropometric index that divides waist circumference by standing…
- Macronutrients (Macros) Macronutrients (macros) are the energy-yielding nutrients protein, carbohydrate, and fat that supply nearly…
- Protein Intake Protein intake is the daily amount of dietary protein consumed to supply amino acids for tissue repair,…
- Water Intake Water intake is the volume of fluid you obtain from beverages and moisture in food to replace losses from…
- Sleep Cycle A sleep cycle is a roughly ninety-minute progression through non-REM stages (light to deep slow-wave sleep)…
- Chronotype Chronotype is your biological preference for sleep and wake timing along a continuum from strong morning…
- Resting Heart Rate (RHR) Resting heart rate (RHR) is the number of heartbeats per minute measured when you are awake, calm, and not…
- Biological Age Biological age is an estimate of how your body’s systems are aging relative to chronological age measured in…
- Burnout Burnout is an occupational phenomenon described by the World Health Organization as resulting from chronic…
- Stress Load Stress load is the cumulative physiological and psychological demand placed on you by acute pressures,…
- Ideal Weight Ideal weight is a contested estimate of a body mass thought to align with lower average health risk or…
- Calorie Deficit A calorie deficit exists when average energy intake is lower than average total daily energy expenditure,…
- Calorie Surplus A calorie surplus exists when average intake exceeds average expenditure, providing extra energy that can…
- Sedentary Behavior Sedentary behavior is waking time spent sitting or reclining with low energy expenditure—typically ≤1.5…
- Steps-to-Calories Conversion Steps-to-calories conversion estimates how much energy walking or running a given step count expends,…
- Weight Loss Rate Weight loss rate is the speed at which body mass declines over days or weeks, usually expressed as kilograms…
- Muscle-Gain Surplus A muscle-gain surplus is a deliberately modest calorie surplus combined with progressive resistance training…
- Metabolic Adaptation Metabolic adaptation refers to reductions in energy expenditure and physiological shifts that occur during…
Productivity
- Decision Fatigue Decision fatigue is the progressive decline in decision quality and willpower-like control after making many…
- Focus Score A focus score is a composite self-assessment or quiz-derived index estimating how well you sustain attention…
- Time Waste Time waste is the portion of working hours spent on low-value activities that neither advance goals nor…
- Procrastination Cost Procrastination cost is the quantified downside of delaying an intentional task—combining late fees,…
- Habit ROI Habit ROI (return on investment) estimates the long-run value of installing a repeatable behavior relative…
- Goal Breakdown Goal breakdown is the practice of decomposing a large outcome into sequenced milestones, projects, and next…
- Daily Energy Management Daily energy management is the deliberate allocation of high-cognitive tasks, admin work, recovery, and…
- Promotion Readiness Promotion readiness is an evidence-based estimate of how prepared you are to perform at the next level,…
- Context Switching Context switching is the cognitive cost of shifting attention between unrelated tasks, projects, or tools,…
- Parkinson's Law Parkinson’s law is the adage that work expands to fill the time available for its completion, coined by…
Money
- Hourly Rate Hourly rate is the amount of money you effectively earn—or should charge—per hour of work after accounting…
- Freelance Pricing Freelance pricing is the method of setting fees for independent work—hourly, day rate, project-based,…
- Savings Rate Savings rate is the percentage of income you keep after spending—typically savings and investments divided…
- Savings Timeline A savings timeline estimates how long it will take to reach a target balance given starting principal,…
- Meeting Cost Meeting cost is the fully loaded expense of gathering people—summing attendees’ effective hourly rates times…
- Money Leak A money leak is recurring spending that drains cash without matching current priorities—unused…
- Skill ROI Skill ROI estimates the financial return from acquiring or deepening a professional skill relative to the…
- Learning ROI Learning ROI broadens skill ROI to evaluate any structured learning investment—books, cohorts, degrees,…
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