Health Tools
Free health tools — BMI calculator, calorie tracker, water reminder, and wellness utilities for a healthier life.
About Health Tools
Health calculators — BMI, BMR via Mifflin-St Jeor, TDEE with activity multipliers, body fat, heart-rate zones, ovulation windows, and calorie needs. All math runs locally; no health data ever leaves your browser.
BMI Calculator
Computes Body Mass Index from metric or imperial height and weight inputs, categorizing the result into underweight, normal, overweight, and obese, with a healthy weight range for your height. Health data never leaves your device — every calculation runs locally in your browser.
Body Fat Percentage Calculator
Calculate body fat percentage using the US Navy circumference method. Enter waist, neck, height, and hip measurements. Health data never leaves your device — every calculation runs locally in your browser.
Body Fat Estimator
Estimate body fat percentage from BMI with an age and gender adjustment. Enter BMI, age, and gender for a quick estimate. Health data never leaves your device — every calculation runs locally in your browser.
Daily Calorie Needs
Calculate your daily calorie needs from BMR (Mifflin-St Jeor) times activity level. Shows basal burn plus maintenance calories for fitness planning. Health data never leaves your device — every calculation runs locally in your browser.
Ideal Body Weight
Compute healthy weight range with Devine and Robinson formulas from height. See a 170 cm target band instantly — free, local, informational only.
Lean Body Mass Calculator
Estimate lean body mass from weight and height with Boer and James formulas averaged — the number training actually moves. Track muscle, not just scale weight — free, local, informational only.
Waist-to-Hip Ratio Calculator
Calculate your waist-to-hip ratio and assess health risk based on your measurements and gender. Health data never leaves your device — every calculation runs locally in your browser.
BMR Calculator
Calculates Basal Metabolic Rate using the Mifflin-St Jeor equation with age, sex, height, and weight. Nutritionists use it for diet planning. Health data never leaves your device — every calculation runs locally in your browser.
BMI Calculator for Kids
Compute children's BMI from height and weight with metric/imperial inputs and a healthy-range readout for growth tracking. See where a 10-year-old sits — free, local, informational only.
Body Surface Area Calculator
Compute body surface area with four formulas (Mosteller, Du Bois, Haycock, Gehan & George) for medication dosing and physiology. Get m² from height and weight — free, local, informational only.
TDEE Calculator
Calculate your Total Daily Energy Expenditure (TDEE) from BMR and activity level. Find how many calories you burn per day.
Breastfeeding Calorie Calculator
Estimate calories burned making breast milk by baby age and feeding frequency, at ~0.67 kcal per mL. Fuel milk production without guessing — free, local, informational only.
Protein Calculator
Compute daily protein needs from weight, goal, and activity — lifters to dieters covered. Hit 120g without guessing portions — free, local, informational only.
Keto Calculator
Compute keto daily calories (TDEE minus 500) with protein at 1.8g/kg and fixed 20g net carbs, fat filling the rest. Hit ketosis without math errors — free, local, informational only.
Macro Calculator
Compute daily protein, carb, and fat macro targets from calories and your own percentage split. Turn any diet into gram numbers — free, local, informational only.
30/40/30 Macro Split
Split calories into protein, carb, and fat grams for any diet target. Turn 2000 kcal into exact macros — free, local, no signup.
Calories Burned Calculator
Estimate workout burn across running, cycling, swimming, yoga, and lifting from weight and duration. Price a 45-minute run in calories — free, local, estimate only.
Calorie Tracker
Log daily calories with one-tap common foods and a running total — simple intake tracking that works. See the day add up as you eat — free, local, no signup.
Steps to Calories Calculator
Convert step counts to calorie burn with weight-adjusted math. Learn what 12,000 steps really cost — free, local, estimate only.
Heart Rate Zone Calculator
Calculate heart rate training zones by age. Find your target heart rate ranges for different exercise intensity levels. Health data never leaves your device — every calculation runs locally in your browser.
Steps to Distance
Convert step counts to kilometers and miles plus calorie estimates from height-based stride. Log daily steps with distance context — free, local, no signup.
Running Pace Calculator
Compute running pace and speed from distance and time in km or miles. Check splits for a 5K tune-up — free, local, no signup.
Cycling Calorie Calculator
Estimate cycling burn from weight, speed, and distance with speed-based MET bands. Price a 40 km weekend ride in calories — free, local, estimate only.
Pregnancy Due Date Calculator
Estimate due date from last period with trimester milestones. Get the 40-week roadmap instantly — free, local, informational only.
Ovulation Tracker
Track your fertile window and estimated ovulation date based on your last menstrual period. Helps with family planning. Health data never leaves your device — every calculation runs locally in your browser.
Baby Formula Calculator
Calculate infant formula amounts by age and weight with feeding schedules. Get daily ounces and bottle splits right — free, local, informational only.
Baby Growth Percentile Calculator
Compare baby weight and height against WHO median references by age and sex, shown as % above or below the median — a reference comparison, not clinical percentiles. Monitor your childs growth compared to population medians. Health data never leaves your device — every calculation runs locally in your browser.
Baby Sleep Schedule Calculator
Build age-appropriate baby sleep schedules — naps, bedtimes, wake windows. End the 5am party phase with structure — free, local, informational only.
Child Height Predictor
Estimate a child's adult height from parents' heights with the mid-parental method. Get a ±8 cm range in seconds — free, local, estimate only.
Blood Alcohol Estimator
Estimate your blood alcohol concentration (BAC) based on drinks consumed, weight, gender, and time elapsed. For educational purposes only. Health data never leaves your device — every calculation runs locally in your browser.
Sleep Requirements
Get recommended sleep hours based on your age. Follows CDC and National Sleep Foundation guidelines from newborn to senior. Health data never leaves your device — every calculation runs locally in your browser.
Water Intake Calculator
Compute daily water needs from weight, activity, and climate. Drink the right amount, not 8 glasses blindly — free, local, no signup.
Sleep Calculator
Compute ideal sleep bedtimes counting back in 90-minute cycles — whole and half-cycle rows (2 to 5 cycles) minus a 15-minute buffer. Wake refreshed at cycle ends, not mid-dream — free, local, no signup.
More from Toolzum
✓ Wellness math runs locally; estimates are informational, not medical advice.
Works fully offline after first load — nothing leaves your browser.
Health FAQs
Is BMI accurate for muscular people?
Not always — BMI can't distinguish muscle from fat, so athletes can read as overweight. Pair it with body-fat estimate and waist-to-height ratio (keep under 0.5) for a fuller picture.
How is BMR calculated?
With the Mifflin-St Jeor equation from weight, height, age, and sex — currently the most validated formula for resting calorie burn. Multiply by an activity factor (1.2–1.9) for TDEE.
What are heart-rate zones for cardio?
Zone 2 (60–70% of max) builds aerobic base and burns fat efficiently; Zone 4–5 (80–100%) builds speed. Max is roughly 220 minus age — the calculators derive all five zones from it.
Is my health data sent anywhere?
No. Every health calculator runs its math locally in your browser — weight, age, and measurements never leave your device.