Util Monster Free

💪 Health & Fitness Calculators

Tools for healthy living and effective exercise

Body Composition

Calculate Body Mass Index (BMI) with WHO classification. Includes healthy weight range, BMI Prime, and Ponderal Index.

Body Fat Calculator

Calculate body fat percentage using Navy Method or BMI Method. Includes fat mass, lean mass, category classification, and ideal ranges.

Lean Body Mass Calculator

Calculate lean body mass (muscle mass) from weight and body fat percentage. Useful for healthy body composition goals (2026)

Ideal Weight Calculator

Calculate ideal weight using Robinson, Miller, Devine, and Hamwi formulas. Compare 4 scientific formulas with BMI healthy range.

FFMI Calculator

Calculate Fat-Free Mass Index to assess muscle mass level. Useful for determining natural muscle growth limits (2026)

Calculate Body Surface Area using 5 formulas (DuBois, Mosteller, etc.). Essential for drug dosage calculation (2026)

Height Percentile Calculator

Calculate what percentile your height is in. Based on Korean average height data (2026)

Child Height Predictor

Predict adult height based on parents' height or current child height. Includes growth curve percentile analysis (2026)

Pants Size Calculator

Convert waist, hip, and inseam measurements to Korean, US, European, and Japanese sizes. Gender-specific size recommendations (2026)

Shoe Size Calculator

Convert foot length to Korean, US, European, Japanese, and Chinese shoe sizes. Men's and women's sizing supported (2026)

Metabolism & Nutrition

BMR & Calorie Calculator

Calculate basal metabolic rate (BMR) and required calories. Supports Mifflin-St Jeor, Harris-Benedict, and Katch-McArdle formulas.

Calorie Calculator

Calculate goal-based calories, zigzag calorie cycling, and macronutrient distribution. Plan meals for weight loss or gain goals.

Daily Protein Calculator

Calculate recommended daily protein intake based on weight, activity level, and goals. Helps with meal planning (2026)

TDEE Calculator

Calculate Total Daily Energy Expenditure, goal-based calories, and macronutrient recommendations (2026)

Daily Water Intake Calculator

Calculate recommended daily water intake based on weight, activity level, and climate. Shows in cups, glasses, and liters (2026)

Daily Vitamin Calculator

Calculate recommended daily allowance (RDA) for 11 vitamins based on age, gender, and lifestyle (2026)

Daily Caffeine Calculator

Calculate total caffeine intake from beverages and check safety limits. Includes coffee, tea, energy drinks (2026)

Macro Calculator

Calculate daily recommended carb, protein, and fat intake based on weight, goal, and activity level. Ratios for cutting, bulking, and maintenance (2026)

Exercise & Training

Heart Rate Calculator

Calculate recommended heart rate based on age and exercise goals.

Exercise Calorie Calculator

Calculate calories burned by exercise type, duration, and weight. Accurate calculation based on MET index (2026)

Calculate one-rep max from reps and weight. For bench press, squat, deadlift, etc. (2026)

Running Pace Calculator

Auto-calculate pace per km and average speed from target distance and time (2026)

Exercise/rest repeat timer. Perfect for HIIT, Tabata, stretching. Sound alerts supported (2026)

Food vs Exercise Comparator

How long to run after eating a whole chicken? Calculate exercise time needed to burn food calories (2026)

Steps Calorie Calculator

Calculate calories burned and distance traveled from steps, weight, and stride. Track 10,000-step goal (2026)

Sleep & Wellness

Sleep Cycle Calculator

Calculate optimal bedtime/wake time considering 90-minute sleep cycles. Recommends 4-6 cycles (2026)

Biorhythm Calculator

Calculate physical, emotional, and intellectual biorhythms. 23, 28, 33-day cycle analysis (2026)

Heat Index Calculator

Calculate feels-like temperature considering temperature, humidity, and wind speed. Includes heat index and wind chill (2026)

Ovulation Calculator

Calculate your ovulation date and fertile window from the start date of your last period and cycle length.

Blood Alcohol Content (BAC) Calculator

Estimate blood alcohol content (BAC) from weight, gender, drinks consumed, and elapsed time. (For reference only — never use to decide whether to drive.)

Wind Chill & Dew Point Calculator

Calculate wind chill (feels-like temperature) from air temperature and wind speed, and dew point from temperature and humidity.

Life Expectancy Calculator

Estimate life expectancy from lifestyle factors like smoking, exercise, diet, and sleep. An illustrative reference tool — not a medical prediction.

Pregnancy Weight Gain Calculator

Find your recommended total pregnancy weight gain range (IOM guidelines) from your pre-pregnancy height and weight or BMI. Singleton pregnancies only. For reference — consult your doctor.

Everyday Tools

Expiry Date Calculator

Calculate expiration date and remaining days from manufacture date and shelf life. Shows freshness status and storage tips (2026)

Batting Average Calculator

Calculate batting average, OBP, slugging, and OPS from at-bats, hits, walks, etc. Includes performance analysis and improvement tips (2026)

Clinical Scores

Wells Score Calculator (DVT/PE)

Wells' Criteria Calculator - Score the 9-item DVT and 7-item PE clinical prediction rules and see the risk tier. Educational reference tool for use alongside professional medical advice.

Glasgow Coma Scale (GCS) Calculator

GCS Calculator - Enter eye-opening, verbal, and motor response scores to get the total consciousness level (3-15) and severity. In an emergency, always follow trained medical personnel.

Apgar Score Calculator

Apgar Score Calculator - Score appearance, pulse, grimace, activity, and respiration to check a newborn's status at 1 and 5 minutes. Actual assessment and care must be performed by medical staff.

Cooper Test (12-Minute Run) Calculator

Cooper Test (12-minute run) Calculator - Enter your 12-minute run distance to estimate VO2max and see your age/gender-based fitness category.

Rockport Walk Test Calculator

Rockport 1-Mile Walk Test Calculator - Enter walk time, heart rate, weight, age, and gender to estimate VO2max. A low-impact aerobic fitness assessment tool.

ANC (Absolute Neutrophil Count) Calculator

ANC (Absolute Neutrophil Count) Calculator - Enter WBC count and segmented/band neutrophil percentages to calculate ANC and check the neutropenia grade (mild/moderate/severe).

Carb-to-Insulin Ratio (ICR) Calculator

Carb-to-Insulin Ratio Calculator - Enter your Total Daily Dose (TDD) of insulin to estimate carbs covered per unit using the 500 Rule (or 450 Rule). Always consult your doctor before changing any dose.

Insulin Sensitivity Factor (ISF) Calculator

Insulin Sensitivity Factor (ISF/correction factor) Calculator - Enter your Total Daily Dose (TDD) to estimate correction-dose effect using the 1800 Rule (rapid-acting) or 1500 Rule (regular). Always consult your doctor before changing any dose.

Blood Glucose Unit Converter

Blood Glucose Converter - Instantly convert between mg/dL and mmol/L in both directions, plus a reference table for HbA1c (A1C) to eAG (estimated Average Glucose).