Health Calculators(25)
BMI, BMR, calorie and other health calculators
BMI Calculator
Check your body mass index (BMI) and weight status.
BMR Calculator
Calculate your basal metabolic rate and daily calorie needs.
Water Intake Calculator
Calculate daily recommended water intake based on weight and activity.
Body Fat Calculator
Estimate body fat percentage using the US Navy method.
Ideal Weight Calculator
Calculate ideal weight range based on height and gender.
Target Heart Rate Calculator
Calculate target heart rate zones by exercise intensity.
Blood Alcohol Calculator
Estimate blood alcohol concentration (BAC) from drinks consumed.
Sleep Calculator
Calculate optimal wake-up and bedtimes based on sleep cycles.
Daily Calorie Calculator
Calculate total daily energy expenditure.
Children BMI Calculator
Calculate children BMI percentile.
Waist-Hip Ratio Calculator
Assess health risk with WHR.
Blood Pressure Calculator
Classify blood pressure readings.
Medication Dosage Calculator
Calculate medication dosage by weight.
Child Fever Medicine Dose Calculator
Calculate a child's acetaminophen/ibuprofen syrup dose and interval by body weight.
Child Daily Water Intake Calculator
Calculate a child's daily maintenance fluid needs by weight using the Holliday-Segar method.
Corrected Age Calculator
Calculate a preterm baby's chronological and corrected age from birth date and gestational age at birth.
Child Daily Calorie Needs Calculator
Calculate a child's estimated energy requirement (EER) from age, sex, weight, height, and activity level.
Body Surface Area (BSA) Calculator
Calculate body surface area (BSA) from height and weight using the Mosteller, DuBois, and Haycock formulas.
Apgar Score Calculator
Calculate a newborn's 1- and 5-minute Apgar score from heart rate, respiration, muscle tone, reflex response, and skin color.
Target Weight Date Calculator
Calculate how long it takes to reach your target weight and the expected date from your weekly loss goal.
Child Predicted Height Calculator
Estimate a child's adult height and range from parents' heights using the mid-parental method.
Vision Calculator
Convert diopter to visual acuity.
Smoking Cost Calculator
Calculate smoking costs.
Health Insurance Premium Calculator
Calculate health insurance premium and long-term care insurance for employees and self-employed.
Blood Sugar Calculator
Assess blood sugar status with fasting glucose, post-meal glucose, and HbA1c.
Overview
The CalKit Health category provides essential calculators for everyday wellness management, including Body Mass Index (BMI), Basal Metabolic Rate (BMR), body fat percentage, ideal weight, daily water intake, target heart rate zones, blood alcohol concentration (BAC), and optimal sleep timing. Every calculator is powered by medically established formulas such as Harris-Benedict, the U.S. Navy body fat method, the Karvonen formula, and the Widmark equation, delivering instant results once you enter personal details like gender, age, height, and weight. Tracking your health metrics regularly can significantly improve weight management, dietary planning, and exercise programming. Please note that all results are for informational purposes only and should not replace professional medical advice. CalKit supports both Korean and English, making it accessible to a wide audience seeking reliable health insights.
Tips
- ✔BMI does not account for muscle mass, so use it alongside the body fat calculator for a more complete picture of your body composition.
- ✔BMR represents calories burned at complete rest; multiply it by an activity factor to get your Total Daily Energy Expenditure (TDEE) for realistic calorie planning.
- ✔Daily water needs vary with body weight, climate, and exercise intensity — aim to drink consistently throughout the day rather than waiting until you feel thirsty.
- ✔Ideal weight ranges depend on frame size and muscle mass in addition to height, so treat them as a general guideline rather than an absolute target.
- ✔Target heart rate zones range from 50% to 85% of your maximum heart rate; beginners should start in the lower zone and gradually increase intensity over time.
- ✔Blood alcohol concentration estimates are approximations — never rely solely on a calculator to decide whether it is safe to drive after drinking.
- ✔Sleep cycles last roughly 90 minutes each, so timing your alarm to coincide with the end of a cycle can help you wake up feeling more refreshed.
- ✔Recording your health calculator results regularly helps you track long-term trends and make more informed lifestyle decisions.
FAQ
Q. Can I have a normal BMI but a high body fat percentage?
Yes. BMI is calculated solely from height and weight, so it cannot distinguish between muscle and fat. A person with low muscle mass and high body fat — sometimes called 'skinny fat' — may show a normal BMI while having an elevated body fat percentage. Using both the BMI and body fat calculators together gives a more accurate assessment.
Q. What is the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the minimum number of calories your body needs at complete rest just to maintain vital functions. TDEE (Total Daily Energy Expenditure) adds the calories burned through daily activities and exercise on top of BMR. When planning a diet, TDEE is the more practical reference point for setting calorie targets.
Q. How much water should I drink per day?
A common guideline is approximately 30 to 35 mL per kilogram of body weight. For a 70 kg adult, this translates to roughly 2.1 to 2.5 liters per day. However, exercise, hot weather, and certain medical conditions can increase your needs. Use CalKit's water intake calculator to get a personalized recommendation.
Q. Can I use the blood alcohol calculator to decide if I am safe to drive?
No. The blood alcohol concentration calculator provides estimates based on the Widmark formula and cannot account for individual factors such as liver function, stomach contents, and medication use. Actual BAC may differ significantly from the estimate. Always follow local legal limits and, when in doubt, use a designated driver or public transportation.
Q. The sleep calculator recommends times that differ from my usual sleep pattern. What should I do?
The sleep calculator bases its suggestions on an average 90-minute sleep cycle. Because individual cycle lengths can vary, treat the results as a starting point and experiment over one to two weeks to discover the schedule that leaves you feeling most rested.
Q. How do I measure my resting heart rate for the target heart rate calculator?
The most accurate method is to count your pulse at your wrist or neck for 60 seconds immediately after waking up in the morning, before getting out of bed. You can also use a smartwatch or chest-strap heart rate monitor. Averaging measurements over at least three days provides a more reliable baseline.
Related Categories
Fitness calculators for calories burned, 1RM, and exercise planning work hand-in-hand with health metrics to build effective workout routines.
Pairing BMR and calorie data with food and nutrition calculators makes it easier to plan balanced meals and manage dietary intake.
During pregnancy, tracking changes in ideal weight, calorie needs, and hydration is essential, making the health and pregnancy categories a natural pair.