Health Calculators 2026 - BMI, TDEE, Pregnancy, Calorie
What makes the health category useful
This category groups calculators that solve closely related real-world tasks, so you can move from a quick estimate to a more specific planning tool without restarting the process.
Track BMI, body fat, lean mass, and weight goals using validated body composition formulas
Calculate TDEE, calorie surplus, and macro targets to plan cutting or bulking phases
Predict pregnancy due date, gestational age, and ovulation window from your cycle data
Run clinical scoring like cardiovascular risk, anion gap, and corrected calcium
Plan sleep cycles, recovery, and one rep max strength targets for training
Weight and nutrition
Calculate BMI, TDEE, and macros to set realistic weekly weight goals based on your activity level.
Pregnancy and fertility
Estimate due date, gestational age, ovulation, and IVF transfer timing from your last period.
Clinical and lab work
Apply medical scoring (anion gap, corrected calcium, cardiovascular risk) for clinical use.
Pregnancy and Fertility
22Corrected Age Calculator
Compute corrected age from birth and due dates.
Gestational Age Calculator
Estimate gestational age from reference date.
Pregnancy Weight Gain Calculator
Recommended pregnancy weight gain.
Trimester Calculator
Identify your current trimester.
Breastfeeding Calorie Calculator
Calories for breastfeeding.
Menstrual Cycle Length Calculator
Average cycle length.
Fertile Window Calculator
Identify fertile days.
Conception Date Calculator
Find out when you conceived from your due date or LMP.
When Was I Conceived Calculator
Enter your birthday to find your estimated conception date.
Retroactive Pregnancy Calculator
Reverse-calculate conception date and pregnancy timeline from due date or birth date.
IVF Due Date Calculator
Due date for IVF.
Pregnancy Week Calculator by Due Date
Find your current pregnancy week from your due date.
Pregnancy Month Calculator
Convert pregnancy weeks to months and track progress.
Period and Ovulation Calculator
Predict period and ovulation dates from your last period.
Irregular Period Ovulation Calculator
Fertile window estimate for irregular cycles.
Due Date from Ovulation Calculator
Convert ovulation date to estimated due date.
Ovulation Calculator After Miscarriage
Estimate ovulation return after pregnancy loss.
Days Past Ovulation Calculator
Track DPO during the two-week wait.
Pregnancy Nutrition Calculator
Daily calories and nutrients by trimester.
Pregnancy Due Date Calculator
Pregnancy due date estimator.
Ovulation Calculator
Ovulation and fertile window estimate.
IVF Calculator
IVF success estimate model.
Body Composition
8Body Surface Area Calculator
BSA for clinical dosing.
Adjusted Body Weight Calculator
AdjBW for drug dosing.
Lean Body Mass Calculator
LBM and body composition.
Weight Loss Percentage Calculator
Weight loss progress %.
Waist-to-Height Ratio Calculator
Waist / Height ratio.
Child BMI Calculator
BMI for children and teens.
Weight-for-Height Growth Calculator
Weight relative to height.
BMI to Body Fat Calculator
Body fat percent from BMI.
Nutrition and Metabolism
17Creatine Loading and Maintenance Calculator
Calculate personalized creatine loading and maintenance doses based on lean body mass.
Gallbladder GSD Risk Index
Gallstone risk and biliary saturation predictor.
Protein Needs Calculator
Daily protein targets.
Calorie Deficit Calculator
Daily deficit for weight loss.
Weight Loss Timeline Calculator
Weeks to your goal weight at any pace.
Meal Calorie Calculator
Total meal calories from macros.
Recipe Nutrition Calculator
Per-serving calories and macros from any recipe.
Carbs to Calories Calculator
Carbohydrate grams to calories converter.
Fat Loss Calculator
Pounds of fat to lose for your target body fat percent.
Body Recomposition Calculator
Build muscle and lose fat at the same time.
Diabetes Carb Calculator
Insulin bolus from carbs and blood sugar.
Protein Requirement Calculator
Daily protein goals.
Tube Feeding and Enteral Nutrition Calculator
Pump rate and volume for enteral tube feeding.
Fiber Intake Calculator
Daily fiber target by age and sex.
Sodium Intake Calculator
Daily sodium and salt limit.
Sugar Intake Calculator
Daily added sugar limit.
Macro and Sleep Sync Calculator
Fat loss macros for early workouts and sleep timing.
Medication and Dosing
14Antibiotic Resistance Predictor
Visualize the risk of missing antibiotic doses and resistance development.
Panadeine Safety and Buffer Tracker
Paracetamol/Codeine toxicity and safety dashboard.
IV Drip Rate Calculator
IV flow rate in gtt/min.
Paediatric Dosage Calculator
Child drug dose by weight/age.
Dosage Calculator
Basic medication dose calculation (D/H * V).
Infusion Rate Calculator
IV pump rate in mL/hr.
Medication Dosage by Weight Calculator
Weight-based dosing (mg/kg).
Paracetamol Dosage Calculator
Pediatric paracetamol dose.
Amoxicillin Dosage Calculator
Pediatric amoxicillin dose by weight with liquid suspension volumes.
Ibuprofen Dosage Calculator for Children
Pediatric ibuprofen dose by weight with liquid volumes for Advil and Motrin.
Benadryl Dosage Calculator for Children
Pediatric Benadryl (diphenhydramine) dose by weight for allergies and hives.
Azithromycin Dosage Calculator for Children
Pediatric azithromycin (Zithromax) dose by weight for 5-day and 3-day protocols.
Insulin Dose Calculator
Correction and carb insulin dose.
Medication Unit Converter
Convert mcg, mg, g, kg for medications.
Lab Values and Kidney
14Renal Angina Index (RAI) Calculator
Predict early AKI risk using risk factors and kidney injury signs.
Corrected Calcium Calculator
Corrected calcium for hypoalbuminemia.
Anion Gap Calculator
Serum anion gap for metabolic acidosis.
Kidney Health and CKD Risk Calculator
Calculate kidney function % and CKD risk.
eGFR Calculator (MDRD)
Estimated GFR for kidney function.
BUN Creatinine Ratio Calculator
BUN/Cr ratio for AKI cause.
FeNa Calculator
FeNa for renal vs pre-renal AKI.
Urine Output Calculator
Urine output in mL/kg/hr.
Serum Osmolality Calculator
Calculated Osmolality.
Transferrin Saturation Calculator
TSAT percentage calculation.
Creatinine Clearance (CrCl) Calculator
Cockcroft-Gault CrCl for drug dosing and kidney function.
Biological Age Calculator (PhenoAge)
Estimate biological age from blood biomarkers using PhenoAge.
UFR Crystal-Predictor and Saturation Index
Predict mineral precipitation and crystalluria risk from UFR data.
Urine Osmolality Calculator (Bogart Formula)
Estimate urine osmolality from specific gravity using the Bogart formulas.
Electrolytes and Fluids
6Percent Dehydration Calculator
Dehydration % assessment.
Corrected Sodium Calculator
Sodium correction for glucose.
Fluid Deficit Calculator
Free water deficit for hypernatremia.
Sodium Deficit Calculator
Total sodium deficit.
Potassium Deficit Calculator
Calculate K+ deficit.
Magnesium Deficit Calculator
Magnesium replacement guide.
Cardiovascular
10Valvular Hemodynamic Load and Stress Estimator
Calculate heart valve stress, VSI, and hemodynamic load.
QTc Calculator
ECG heart rate correction.
Target Heart Rate Calculator
Exercise heart rate zones.
Pulse Pressure Calculator
SBP - DBP difference.
CHA2DS2-VASc Score
AFib Stroke Risk Score.
HAS-BLED Score
Major Bleeding Risk Score.
Shock Index Calculator
Early warning hemodynamic shock index (HR/SBP) calculator.
Mean Arterial Pressure (MAP) Calculator
Average arterial pressure.
Heart Rate Calculator
BPM from intervals.
Vagal Tone (HRV) Recovery Modeler
HRV-based Vagal Tone and recovery modeler.
Respiratory
9Lungs: Biological Lung-Age and PEF Estimator
Estimate your biological lung age from Peak Flow (PEF) readings.
A-a Gradient Calculator
Alveolar-arterial oxygen gap.
Oxygen Requirement Calculator
Flow to FiO2 estimation.
A-a Gradient Calculator
Determine A-a gradient.
PaO2/FiO2 Ratio Calculator
P/F Ratio for ARDS.
Alveolar Gas Equation Calculator
Calculate Alveolar Oxygen (PAO2).
Minute Ventilation Calculator
RR * Tidal Volume.
Predicted Peak Flow Calculator
Expected PEF for asthma.
Respiratory Rate Calculator
Calculate RR from timed count.
Diabetes and Blood Sugar
7HbA1c to eAG Calculator
A1c to Average Glucose.
Blood Sugar Conversion Calculator
mg/dL to mmol/L conversion.
Insulin Correction Dose Calculator
Correction dose estimation.
Carbohydrate Ratio Calculator
Calculate Insulin-to-Carb ratio.
HOMA-IR Calculator
Identify Insulin Resistance.
METS-IR Calculator (Insulin Action Profiler)
Screen for insulin resistance without an insulin test.
TyG Index Calculator (Triglyceride-Glucose Index)
Calculate TyG Index for insulin resistance and metabolic risk assessment.
Clinical Scoring
15Cancer Risk Calculator
Assess cancer risk from lifestyle, genetics, and medical factors.
Spleen and Blood: NLR Systemic Inflammation Profiler
Calculate systemic inflammation and immune resilience from CBC.
MELD Score Calculator
MELD-Na for liver disease severity.
NIHSS Calculator
NIHSS total 0 to 42.
HEART Score Calculator
HEART score 0 to 10 for chest pain.
Child-Pugh Score Calculator
Child-Pugh class A, B, or C.
APGAR Score Calculator
Newborn health assessment.
Glasgow Coma Scale (GCS) Calculator
Neurological assessment scoring.
NEWS2 Score Calculator
Official RCP National Early Warning Score (NEWS2) tool.
qSOFA and SOFA Calculator
Sepsis risk assessment.
CURB-65 Pneumonia Score
Pneumonia severity scoring.
Wells Score (DVT and PE)
Blood clot probability scoring.
PERC Rule Calculator
PE Rule-out criteria.
CHA₂DS₂-VASc Score for Atrial Fibrillation
Stroke risk in Afib.
Fatty Liver Index (FLI) Calculator
Calculate FLI score for fatty liver and NAFLD risk screening.
General Health
10Sleep Cycle Calculator
Find ideal bedtimes based on 90-minute sleep cycles.
Steps to Kilometers Calculator
Convert steps to distance, calories, and walking time.
ScreenFatigue Digital Eye Strain Index
Predict eye strain risk and 20-20-20 rule schedule.
Digital Eye Strain and Myopia-Shift Predictor
Calculate eye fatigue and myopia-shift risk index.
"Dermal-Safe" UV and Vitamin D Optimizer
Calculate Vitamin D synthesis time and burn risk.
Smoking Pack Year Calculator
Smoking exposure over time.
Parkland Formula Calculator
Burn center fluid volume.
Dopamine Baseline Calculator
Dopamine sensitivity & digital burnout predictor.
Winter's Formula Calculator
Expected PCO2 in Acidosis.
Burn Surface Area and Parkland Formula
Burn resuscitation math.
Related Articles
All articles
Gestational Age vs Due Date: What Is the Difference?
Gestational age vs due date explained in plain language. Learn how weeks pregnant, expected delivery date, LMP, ultrasound, and IVF dating fit together.
Read article
How to Use a Fertile Window Calculator Correctly
Learn how to use a fertile window calculator correctly with cycle length, ovulation timing, sperm survival, and the best days to conceive.
Read article
Biological Age vs Chronological Age: Real Health in 2026
Biological age tracks how fast your body is aging, not just how many birthdays you have had. Learn how it is calculated in 2026 and how to lower it with measurable habits.
Read article
How to Calculate Corrected Age for Premature Babies
Learn how to calculate corrected age for premature babies using birth date, due date, and weeks early. Includes step-by-step examples and milestone guidance.
Read articleCategory FAQ
How is BMI calculated?
BMI equals weight in kilograms divided by height in meters squared. A 70 kg person 1.75 m tall has a BMI of 70 divided by (1.75 times 1.75), which equals 22.9, classified as normal weight (18.5 to 24.9).
How many calories do I need to lose 1 pound a week?
A 500 calorie daily deficit creates a 3,500 calorie weekly deficit, which is roughly 1 pound (0.45 kg) of fat. Use the TDEE calculator to find your maintenance calories first, then subtract 500 for steady weekly loss.
How is the pregnancy due date calculated?
Naegele rule: due date equals first day of last menstrual period plus 280 days (40 weeks). The pregnancy due date calculator also adjusts for known conception or IVF transfer dates.
What is a healthy resting heart rate?
Most adults rest at 60 to 100 beats per minute. Trained athletes can sit in the 40 to 60 range. Resting rates above 100 bpm warrant a check with a clinician.
How accurate are these health calculators?
Tools use validated medical formulas (Mifflin-St Jeor for TDEE, NHS BMI bands, Naegele for due dates, AHA PREVENT for cardiovascular risk). They estimate, not diagnose, and do not replace clinical advice.
How do I calculate my one rep max?
Estimate using the Epley formula: 1RM equals weight times (1 plus reps divided by 30). 100 kg lifted for 5 reps gives a 1RM of 100 times (1 plus 5 divided by 30), which equals about 116.7 kg.
Modern Tools for Every Need
Secure and Private
All calculations run locally. Your data never leaves your browser.
Verified Precision
Precise Calculations Powered by Calculory AI