❤️Health & Fitness
BMI, calorie, TDEE, macro, and body composition calculators.
Browse health and fitness calculators for daily planning, body metrics, training, recovery, and routine wellness questions. This category includes tools for BMI, calories, TDEE, macros, body fat, BMR, protein, water intake, running pace, heart-rate zones, sleep timing, due dates, ovulation estimates, and other health-related calculations people use to make sense of everyday numbers.
What You'll Find Here
You will find calculators organized around the type of estimate you need. Nutrition and energy tools cover calories, TDEE, BMR, calorie deficit, macros, protein, and water intake. Body measurement tools cover BMI, body fat, ideal weight, waist ratios, and weight gain estimates. Performance tools cover pace, one-rep max, VO2 max, heart-rate zones, steps, and calories burned. Planning tools cover sleep timing, pregnancy due date, ovulation windows, and measurement conversions that come up in health tracking.
All Health & Fitness Tools
BMI Calculator
Use this BMI calculator to check your body mass index based on height and weight. Supports metric and US units with instant results and BMI category.
Open toolRunning Pace Calculator
Calculate running pace, average speed, and finish time from any distance and total time. Useful for 5K, 10K, half marathon, marathon, and training runs.
Open toolSleep Calculator
Use this sleep calculator to estimate bedtime or wake-up options based on 90-minute sleep cycles and a 15-minute fall-asleep buffer.
Open toolTDEE Calculator
Calculate your TDEE and BMR with the Mifflin-St Jeor equation from weight, height, age, sex, and activity level, then plan daily calories for any goal.
Open toolMacro Calculator
Calculate your daily macro targets in grams for protein, carbs, and fat from your calorie goal and chosen macro split, for any diet or training plan.
Open toolBody Fat Calculator
Estimate your body fat percentage from weight, height, age, and sex using a formula-based method, with a result and category for quick reference.
Open toolIdeal Weight Calculator
Estimate ideal body weight from height and sex with the Devine formula. See a practical range in kg or lb and learn how to read the result.
Open toolCalorie Calculator
Estimate your daily calorie needs from age, sex, height, weight, activity level, and goal, for maintaining, losing, or gaining weight at a steady rate.
Open toolPregnancy Due Date Calculator
Use this pregnancy due date calculator to estimate your delivery date from the first day of your last menstrual period, with an estimated conception date and plain-language notes.
Open toolOvulation Calculator
Estimate ovulation date, fertile window, and next period date using last period date and cycle length.
Open toolBMR Calculator
Use this BMR calculator to estimate basal metabolic rate with the Mifflin-St Jeor formula based on sex, age, height, and weight.
Open toolProtein Calculator
Use this protein calculator to estimate daily protein intake from body weight, unit choice, and a maintenance, build, or cut goal.
Open toolWater Intake Calculator
Use this water intake calculator to estimate daily hydration from body weight, activity minutes, and climate assumptions in liters, milliliters, and ounces.
Open toolOne Rep Max Calculator
Use this one rep max calculator to estimate 1RM from lifted weight and reps using the Epley formula.
Open toolCalories Burned Calculator
Use this calories burned calculator to estimate calories burned from activity, body weight, duration, and MET assumptions.
Open toolHeart Rate Zone Calculator
Use this heart rate zone calculator to estimate training heart rate zones using age-based max heart rate and optional resting heart rate.
Open toolCalorie Deficit Calculator
Estimate daily calorie targets from BMR, activity level, and a selected deficit percentage with clear assumptions and realistic planning guidance.
Open toolDog Age Calculator
Convert your dog's age into human years with a size-adjusted method. Enter your dog's age and breed size to get an estimated human age and life stage.
Open toolSteps to Miles Calculator
Convert steps to miles, kilometers, and feet based on your stride length. Find out how many miles 10,000 steps is and how many steps are in a mile.
Open toolHeat Index Calculator
Find the heat index from temperature and humidity. Enter the air temperature in Fahrenheit and the relative humidity to get the feels-like temperature and risk level.
Open toolSteps to Calories Calculator
Use this steps to calories calculator to estimate calories burned from your step count and body weight. 10,000 steps burns about 400 calories.
Open toolVO2 Max Calculator
Estimate your VO2 max from age and resting heart rate. A 30-year-old with a resting heart rate of 60 has an estimated VO2 max of about 48.5 mL/kg/min.
Open toolWaist-to-Hip Ratio Calculator
Use this waist-to-hip ratio calculator to divide waist by hip size and classify the result with standard adult risk bands for men and women.
Open toolmmol/L to mg/dL Converter
Convert blood glucose from mmol/L to mg/dL and back with the glucose factor of 18.0182. Includes worked examples, a quick table, and a cholesterol warning.
Open toolWaist-to-Height Ratio Calculator
Use this waist-to-height ratio calculator to divide waist by height, see the result as a ratio and percent, and compare it with adult screening bands.
Open toolWeight Gain Calculator
Estimate calorie surplus, projected weekly weight gain, and time to goal from maintenance calories, target intake, and your current and target weight.
Open toolPonderal Index Calculator
Use this ponderal index calculator to estimate adult body proportionality from height and weight in metric or US units, with a broad adult reference band and plain-language interpretation.
Open toolHarris-Benedict Calculator
Use the Harris-Benedict calculator to estimate BMR and TDEE with the revised 1984 Harris-Benedict equation and standard activity multipliers.
Open toolRMR Calculator
Use this RMR calculator to estimate resting metabolic rate with the Revised Harris-Benedict equation from age, sex, height, and weight.
Open toolmcg to IU Converter
Convert mcg to IU and IU to mcg for vitamin D, vitamin A retinol, and natural or synthetic vitamin E. Includes label warnings because IU is substance specific.
Open toolIQ Percentile Calculator
Convert an IQ score into an approximate percentile by using a mean of 100 and a selectable standard deviation of 15 or 16, with plain-language notes about the bell-curve model.
Open toolDrops Per Minute Calculator
Estimate a gravity IV drip rate in drops per minute from volume, infusion time, and tubing drop factor. Includes macrodrip and microdrip examples and safety limits.
Open toolBody Shape Calculator
Use this body shape calculator to compare bust, waist, and hip measurements and sort them into broad body-shape categories with a simple ruleset.
Open toolFace Shape Calculator
Use this face shape calculator to compare forehead, cheekbone, jawline, and face-length measurements and estimate your face shape.
Open toolLDL Calculator
Estimate LDL cholesterol from total cholesterol, HDL, and triglycerides with the Friedewald equation in mg/dL. Includes assumptions, common limits, examples, and a medical disclaimer.
Open toolWeight Loss Percentage Calculator
Use this weight loss percentage calculator to compare starting and current weight, then see pounds or kilograms lost and the percent change.
Open toolNavy Body Fat Calculator
Use this Navy body fat calculator to estimate body fat percentage from height, neck, waist, and hip measurements with sex-specific inputs in centimeters or inches.
Open toolMean Arterial Pressure Calculator
Use this mean arterial pressure calculator to estimate MAP from systolic and diastolic blood pressure with the standard resting approximation.
Open toolBRI Calculator
Use this BRI calculator to estimate body roundness index from waist and height, compare the result with broad adult screening bands, and review the assumptions behind the score.
Open toolFFMI Calculator
Use this FFMI calculator to estimate lean mass, fat-free mass index, and normalized FFMI from weight, height, and body fat percentage.
Open toolINR Calculator
Estimate INR from patient prothrombin time, control PT, and reagent ISI with the WHO INR formula. Includes assumptions, common limits, examples, and a medical disclaimer.
Open toolACR Calculator
Calculate the urine albumin-to-creatinine ratio (ACR / UACR) in mg/g from urine albumin and urine creatinine. Choose mg/dL, mg/L, or g/L units and see published interpretation bands with a medical disclaimer.
Open toolCholesterol Units Converter
Convert total, LDL, or HDL cholesterol between mg/dL and mmol/L with the cholesterol factor of 38.67. Includes a lab lookup table and a glucose warning.
Open toolGestational Age Calculator
Estimate gestational age from your last menstrual period. See weeks and days, trimester, percent complete, and the estimated due date from one date check.
Open toolBlood Type Calculator
Enter both parents' ABO type and Rh factor to see every blood type their child could inherit, based on standard Mendelian genetics.
Open toolLean Body Mass Calculator
Use this lean body mass calculator to estimate lean mass and fat mass from weight and height with the sex-specific Boer formula.
Open toolWinning Percentage Calculator
Use this winning percentage calculator to turn any wins, losses, and ties record into a standings-style percentage, the way sports leagues rank teams.
Open toolBatting Average Calculator
Calculate batting average from hits and at-bats. Enter your stats to get AVG in the traditional .300 format, plus the decimal value and outs.
Open toolStride Length Calculator
Estimate your walking or running stride length from your height using standard gender-based multipliers. See stride length in inches and centimeters plus steps per mile.
Open toolBike Size Calculator
Use this bike size calculator to find a recommended frame size range from your height for road, mountain, and hybrid bikes, plus a height band reference table.
Open toolWet Bulb Calculator
Estimate wet-bulb temperature, dew point, and heat stress risk from air temperature and relative humidity. Understand when outdoor conditions become dangerous.
Open toolWalking Calorie Calculator
Find out how many calories walking burns. A 155 lb person walking 30 minutes at 3 mph burns about 129 calories. Uses standard MET values by walking speed.
Open toolNRR Calculator (Net Run Rate)
Calculate cricket net run rate. A team scoring 287 in 50 overs and conceding 243 in 50 has an NRR of +0.880. Handles partial overs the ICC way.
Open toolPuppy Weight Calculator
Estimate your puppy's adult weight from its current weight and age. A 12 lb puppy at 16 weeks projects to about 39 lb full grown. Uses the growth-rate rule.
Open toolSwimming Calorie Calculator
Find out how many calories swimming burns. A 155 lb person swimming freestyle for 30 minutes burns about 214 calories, and butterfly nearly doubles that.
Open toolDesk Height Calculator
Find your ideal desk and chair height from your body height. A 5'9" (175 cm) person needs a sitting desk around 73.5 cm and a standing desk around 108.5 cm.
Open toolStrike Rate Calculator (Cricket)
Calculate cricket strike rate. A batter scoring 45 runs off 32 balls has a strike rate of 140.63. Covers batting (runs per 100 balls) and bowling strike rates.
Open toolDog Pregnancy Calculator
Estimate your dog's due date from the mating date. Canine pregnancy lasts about 63 days, with most litters arriving between day 58 and day 68.
Open toolSunscreen Calculator
Estimate how long sunscreen protects your skin. Fair skin that burns in 15 minutes gets a theoretical 7.5 hours from SPF 30, but reapplication every 2 hours still rules.
Open toolDress Size Calculator
Find your dress size from bust, waist, and hip measurements. A 34.5-26.5-36.5 inch figure is a US 6, UK 10, EU 38. Based on the standard misses chart.
Open toolPower to Weight Ratio Calculator
Calculate power-to-weight ratio for cycling and cars. A 70 kg cyclist holding 280 watts rides at 4.0 W/kg, solid amateur racing form. Cars get hp per tonne.
Open toolJump Rope Calorie Calculator
Find out how many calories jumping rope burns. A 155 lb person skipping at a moderate pace for 15 minutes burns about 218 calories, on par with running.
Open toolJeans Size Calculator
Find your jeans size from a waist measurement. A 27 inch waist matches US 6 (EU 38, UK 10) for women, or 32x32 for men. Covers women's and men's denim charts.
Open toolBiking Calorie Calculator
Find out how many calories cycling burns. A 155 lb rider at 12-13.9 mph for 30 minutes burns about 295 calories. Uses standard MET values by speed.
Open toolRunning Calorie Calculator
Find out how many calories running burns. A 155 lb runner at 6 mph for 30 minutes burns about 362 calories. Uses standard MET values by running speed.
Open toolWeightlifting Calorie Calculator
Estimate calories burned lifting weights from body weight, active minutes, and training intensity. Compare light, moderate, and vigorous MET levels.
Open toolBaby Age Calculator
Find out exactly how old your baby is in weeks and days, months, and years. Enter a birth date and an as-of date for a calendar-accurate age breakdown.
Open toolBSA Calculator (Body Surface Area)
Calculate body surface area in square meters with the Mosteller and Du Bois formulas. Enter height and weight in metric or US units and see both BSA estimates instantly.
Open toolRelative Humidity Calculator
Calculate relative humidity from air temperature and dew point, or work backward from humidity to find the dew point. Uses the Magnus approximation for fast, accurate estimates in Celsius.
Open toolCat Age Calculator
Convert your cat's age to human years. Enter your cat's age to see the human-age equivalent and life stage. Free, no signup.
Open toolCalories Burned Standing Calculator
Estimate how many calories you burn while standing. A 70 kg person standing for 8 hours burns about 1,008 calories using the standard MET value of 1.8.
Open toolDosage Calculator
Estimate pediatric medication dosages using Clark's, Young's, Fried's, and weight-based formulas. This is a reference tool only and not a substitute for professional medical advice.
Open toolTransferrin Saturation Calculator
Calculate transferrin saturation (TSAT) from serum iron and total iron-binding capacity (TIBC). Enter both values in mcg/dL and see general educational reference bands with a medical disclaimer.
Open toolKt/V Calculator
Calculate single-pool Kt/V for hemodialysis adequacy using the Daugirdas second-generation equation from pre- and post-dialysis BUN, session length, ultrafiltration volume, and post-dialysis weight.
Open toolEU/US/UK Shoe Size Converter
Convert shoe sizes between US, EU, UK, and cm. A men's US 9 is EU 42, UK 8, 27 cm. A women's US 8 is EU 39, UK 6, 25 cm. Covers half sizes 5-13 men, 5-11 women.
Open toolHair Growth Calculator
Estimate how long your hair will grow or how many months until it reaches a goal length. Uses the average growth rate of 0.5 inch per month. Free, no signup.
Open toolDuckworth-Lewis (DLS) Calculator
Estimate a DLS-style par score and revised target for a rain-hit cricket match. Enter Team 1's score, overs available, and Team 2's overs and wickets lost.
Open toolFeatured Tools
Duckworth-Lewis (DLS) Calculator
Estimate a DLS-style par score and revised target for a rain-hit cricket match. Enter Team 1's score, overs available, and Team 2's overs and wickets lost.
FeaturedTransferrin Saturation Calculator
Calculate transferrin saturation (TSAT) from serum iron and total iron-binding capacity (TIBC). Enter both values in mcg/dL and see general educational reference bands with a medical disclaimer.
FeaturedKt/V Calculator
Calculate single-pool Kt/V for hemodialysis adequacy using the Daugirdas second-generation equation from pre- and post-dialysis BUN, session length, ultrafiltration volume, and post-dialysis weight.
Grouped by Topic
Health calculators can be useful, but they are not the same as diagnosis or personal medical guidance. Most of these tools use population formulas, estimated activity multipliers, or standard conversion factors, which means two people with the same inputs may still have different real-world outcomes. The safest way to use the result is as a starting point for tracking trends, asking better questions, or comparing scenarios over time. Read the assumptions, note the unit system, and avoid treating a single number as a complete picture of your health. These calculators provide general estimates only and are not medical advice. For personal health decisions, speak with a qualified healthcare professional.
Frequently Asked Questions
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