Health calculators

BMI, BMR, TDEE, macros, FFMI, MET calorie burn, GFR, pregnancy tools, dog helpers, and sleep cycles. Informational, not a diagnosis or medical advice.

36 tools

In this group

Start with BMI. BMR and TDEE use Mifflin-St Jeor. Split calories with macros, or target protein, carbohydrate, and fat alone. Lean-mass density is FFMI. Activity energy uses MET tables on calories burned and the activity-specific pages. One-rep max estimates strength from a submaximal set. GFR uses CKD-EPI 2021. Tape percent is Navy or Army. Pregnancy pages cover due date, conception, and IOM weight-gain ranges. Dog pages cover calories, water, chocolate exposure sketches, and whelping dates. Sleep cycle suggests bed and wake times. None of these pages is medical or veterinary advice.

Adjusted Body Weight Calculator Compute Devine ideal body weight and adjusted body weight from sex, height, and total body weight. When total weight is above IBW, ABW = IBW + 0.4 × (TBW - IBW). Informational, not a prescription.
Army Body Fat Calculator Estimate body-fat percent with the Hodgdon / DoD circumference method, then compare it with an AR 600-9 age-group maximum sketch. Metric tapes convert to inches inside the math. Informational, not an official accession or retention tape.
BMI Calculator BMI = kg / m². US units convert with 1 lb = 0.45359237 kg and 1 in = 0.0254 m. Informational, not a medical diagnosis.
BMR Calculator Basal metabolic rate from Mifflin-St Jeor and revised Harris-Benedict. Optional Katch-McArdle if you type body fat. Not medical advice.
Navy Body Fat Calculator US Navy circumference method. Metric tapes are converted to inches inside the formula. Informational, not an accession tape.
Body Surface Area Calculator Body surface area from height and weight. Primary formula is Mosteller: sqrt(cm * kg / 3600). Du Bois and Haycock are listed as well. Informational, not medical advice and not a dosing chart.
Calories Burned Biking Calculator Estimate kilocalories for a bike ride from MET, body weight, and minutes. Choose leisure, moderate, or vigorous cycling intensity. Informational, not a power-meter readout.
Calories Burned Calculator Estimate how many kilocalories a session burns from MET, body weight, and duration. Pick an activity preset or override MET. Informational, not a lab measurement or medical advice.
Calories Burned Hiking Calculator Estimate kilocalories for a hike from MET, body weight, and minutes. Choose a standard hike or a steeper / pack-loaded effort. Informational, not a trail prescription.
Calories Burned Weight Lifting Calculator Estimate kilocalories for a resistance session from MET, body weight, and minutes. Choose vigorous lifting or a lighter circuit. Informational, not a programming coach.
Calories Burned Running Calculator Estimate kilocalories for a run from MET, body weight, and minutes. Choose easy, typical, or faster pace presets. Informational, not a VO2 lab test.
Calories Burned Swimming Calculator Estimate kilocalories for a swim from MET, body weight, and minutes. Choose leisure, moderate, or vigorous effort in the water. Informational, not a stroke analysis.
Calories Burned Walking Calculator Estimate kilocalories for a walk from MET, body weight, and minutes. Choose a casual ~3 mph walk or a brisk ~3.5 mph walk. Informational, not step-count medical advice.
Carbohydrate Intake Calculator Turn a daily calorie target and a carbohydrate percent into grams using 4 kcal per gram. Default share is 50%. Optional body weight adds a g/kg row. Informational, not a diabetes or diet plan.
Dog Calorie Calculator Estimate a dog's resting energy requirement (RER) with 70 × kg^0.75, then scale to maintenance energy (MER) using life-stage factors such as neutered adult, puppy, senior, or working. Veterinary rule of thumb, not a substitute for a vet feeding plan.
Dog Chocolate Toxicity Calculator Sketch theobromine dose in mg/kg from dog weight, chocolate type, and amount eaten. If a dog ate chocolate, contact a veterinarian or pet poison hotline immediately. Do not wait on a web estimate. This page is not a diagnosis or treatment plan.
Dog Pregnancy Calculator Estimate a whelping date from a breeding (mating) date and a gestation length in days. Default gestation is 63 days; allowed range is 56 to 72. Optional as-of date shows days elapsed and remaining. Breeding-date arithmetic only, not progesterone timing or veterinary care.
Dog Water Intake Calculator Estimate a healthy dog's daily water volume from body weight and a mL per kilogram rate (default 50). Choose normal or active activity; active multiplies by 1.25. Informational sketch only, not care for polydipsia or illness.
Fat Intake Calculator Turn a daily calorie target and a fat percent into grams using 9 kcal per gram. Default share is 30%. Informational, not a cholesterol or diet prescription.
FFMI Calculator FFMI is fat-free mass divided by height squared. Normalized FFMI adjusts that index toward a 1.8 m reference height. Enter height, weight, and a body-fat percent. Informational, not a diagnosis.
Gestational Age Calculator Gestational age from LMP, estimated due date, and trimester. Same 280-day rule as the due-date page.
GFR Calculator Estimate glomerular filtration rate with the race-free CKD-EPI creatinine equation (2021). Enter age, sex, and serum creatinine in mg/dL or umol/L. Informational, not a diagnosis of chronic kidney disease.
Heart Rate Zone Calculator Five zones as percents of estimated max HR. Max HR here is 220 minus age. If you type resting heart rate, zones use Karvonen: rest + percent times (max minus rest). Informational, not medical advice.
Ideal Weight Calculator Devine, Robinson, Miller, and Hamwi ideal-weight formulas, plus the WHO BMI 18.5 to 24.9 band for that height.
Lean Body Mass Calculator Lean mass from a body-fat percent you type, or Boer / James / Hume estimates from height, weight, and sex.
Macro Calculator Split a calorie target into protein, carbohydrate, and fat grams. Protein and carbohydrate use 4 kcal per gram. Fat uses 9 kcal per gram. Percents must sum to 100. Informational, not medical advice and not a diet plan.
One Rep Max Calculator Estimate a one-repetition maximum from a submaximal set. Enter the weight you lifted and how many clean reps you completed (2 to 12). The page shows Epley, Brzycki, Lander, Lombardi, Mayhew, and their average. Informational, not a training prescription.
Ovulation Calculator Estimate ovulation as cycle start plus (cycle length minus 14 days). Also lists a simple fertile window and the next period if the cycle stays constant. Informational, not medical advice. Not contraception.
Pregnancy Conception Calculator Estimate a conception date and a short fertile window from either a due date or a last menstrual period. Rules use LMP + 14 days or due date minus 266 days. Calendar sketch only, not obstetric ultrasound dating.
Due Date Calculator Estimated due date as LMP + 280 days (Naegele), with gestational age and trimester. Not obstetric care.
Pregnancy Weight Gain Calculator Map pre-pregnancy height and weight to IOM gestational weight-gain ranges. Choose singleton or twins tables and optionally compare a gain in pounds. Informational, not prenatal care or medical advice.
Protein Intake Calculator Estimate a daily protein target in grams from body weight and a goal band. Bands cover sedentary, active, strength, athlete, and older-adult ranges. Optionally override grams per kilogram. Informational, not a medical diet.
Sleep Cycle Calculator Suggest bedtimes from a wake time, or wake times from a bedtime, using repeating cycle blocks (default 90 minutes) plus a fall-asleep buffer (default 14 minutes). Shows 6, 5, 4, and 3 cycle options. Informational sketch, not a medical sleep study.
TDEE Calculator TDEE = Mifflin-St Jeor BMR × activity factor. All five common factors are listed. Not a diet prescription.
Waist to Hip Ratio Calculator WHR = waist / hip using the same length unit on both tapes. WHO adult labels differ by sex. Informational, not medical advice and not a diagnosis.
Water Intake Calculator Estimate a daily water volume from body weight, activity level, climate, and a base mL per kilogram rate (default 33). Results appear in liters, milliliters, and US fluid ounces. Informational, not medical advice for illness or kidney disease.