WHWD
Health tools

Quick calculators for everyday health questions.

Estimate body metrics, nutrition targets, and hydration needs with clear educational tools. These calculators are informational and do not replace medical care.

Body metrics

BMI Calculator

Estimate body mass index from height and weight, with a plain-language category.

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Nutrition

BMR Calculator

Estimate resting daily energy needs using the Mifflin-St Jeor equation, with clear context for interpreting your result.

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Nutrition

Daily Calorie Needs Calculator

Estimate maintenance calories and gentle weight-change ranges by activity level.

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Hydration

Water Intake Calculator

Estimate daily fluid needs based on body weight, activity, and warm-weather exposure.

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Nutrition

Protein Intake Calculator

Estimate a daily protein range based on body weight, activity, and goal, with practical context for using the result safely.

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Nutrition

Macro Calculator

Turn a daily calorie estimate into carbohydrate, protein, and fat targets using an adjustable planning pattern.

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Nutrition

Carbohydrate Intake Calculator

Estimate a broad daily carbohydrate range from your calorie target, with context for individual needs.

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Body metrics

Body Fat Percentage Calculator

Estimate adult body fat percentage from circumference measurements using the U.S. Navy method.

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Body metrics

Waist-to-Height Ratio Calculator

Compare waist circumference with height as a simple adult health-screening estimate.

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Fitness

Heart Rate Zone Calculator

Estimate age-based exercise heart-rate zones for walking, running, and cardio workouts, with practical context for safer training plans.

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Sleep

Sleep Calculator

Work backward from a wake-up time to estimate when to get into bed for an adult sleep target.

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Fitness

Walking Calories Calculator

Estimate calories used during a walk from body weight, duration, and walking pace.

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Fitness

Steps to Calories Calculator

Estimate walking distance and calories from your step count, body weight, and height, with practical context for stride length and daily activity.

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Pregnancy

Pregnancy Due Date Calculator

Estimate a pregnancy due date from the first day of the last menstrual period and usual cycle length.

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Pregnancy

Ovulation Calculator

Estimate an ovulation date and fertile window from the first day of the last period and usual cycle length.

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Body metrics

Ideal Weight Range Calculator

Estimate an adult BMI reference weight range from height, with context about the limits of one-size-fits-all targets.

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Lifestyle

Caffeine Intake Calculator

Estimate total daily caffeine from serving count and label amount, then compare it with general adult guidance.

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Lifestyle

Smoking Cost Calculator

Estimate the monthly and yearly cost of cigarettes from daily use, pack size, and local pack price.

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Lifestyle

Alcohol Standard Drink Calculator

Estimate alcohol grams and U.S. standard drinks from beverage volume and alcohol by volume (ABV).

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Prevention

Diabetes Risk Score Tool

Use an ADA-style adult screening checklist to estimate whether diabetes risk and blood testing may be worth discussing.

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