← All Calculators

Blog

Evidence-based articles on health metrics, nutrition, and fitness.

2026-03-25·8 min

Calculate BMI: What the Body Mass Index Really Tells You

Calculate your BMI with the formula, WHO table & interpretation. Learn the limits of BMI and which alternatives exist.

2026-03-25·7 min

Calculate Ideal Weight: What Is the Perfect Weight?

Calculate your ideal weight with four formulas. Devine, Robinson, Miller & Hamwi compared — plus healthy BMI range.

2026-03-25·7 min

Body Fat Percentage Calculator: Navy Method, Charts & Tips

Calculate body fat percentage using the U.S. Navy method. Categories, guidelines and why body fat is more meaningful than BMI.

2026-03-25·7 min

Calculate TDEE: How to Determine Your Daily Calorie Burn

Calculate TDEE using the Mifflin-St Jeor formula. Basal metabolic rate, activity factors and calorie goals for losing or gaining weight.

2026-03-25·7 min

Calculate Macronutrients: How to Split Protein, Carbs & Fat

Calculate macronutrients based on your calorie needs and goals. Optimal distribution for weight loss, maintenance and muscle building.

2026-03-25·6 min

Calculate Water Intake: How Much Water You Need Daily

Calculate daily water intake — adjusted for weight, activity and climate. With glass conversion and practical tips.

2026-03-25·6 min

Calculate Sleep Cycles: Wake Up at the Right Time

Calculate sleep cycles for restful sleep. Understand 90-minute cycles and find your optimal bedtime or wake-up time.

2026-03-26·7 min

Calculate Due Date: When Is My Baby Coming?

Calculate your due date using Naegele's rule. Pregnancy weeks, trimesters, milestones and why only 4% of babies arrive on the estimated date.

2026-03-27·7 min

Calculate Calorie Deficit: How to Lose Weight Safely

Calculate your calorie deficit using the Mifflin-St Jeor formula. TDEE, safe deficit and the 7,700 kcal rule explained simply.

2026-03-25·7 min

Calculate Heart Rate Zones: Train in the Right Range

Calculate the five heart rate zones. Standard and Karvonen methods for targeted training from fat burn to VO2max.

2026-03-27·7 min

Calculate Waist-to-Hip Ratio: WHR, WHO Thresholds & Risk

Calculate your waist-to-hip ratio (WHR) and assess health risk. WHO thresholds, measurement guide and why WHR is more meaningful than BMI.

2026-03-27·7 min

Measure Blood Pressure: Understand & Interpret Your Values

Measure blood pressure correctly and interpret your values. AHA categories, measurement tips, risk factors and when to see a doctor.

2026-03-29·7 min

Calculate Ovulation: How to Determine Your Fertile Days

Calculate your ovulation with the calendar method. Fertile window, cycle length, luteal phase and tips for natural family planning.

2026-03-30·7 min

Calculate Protein Intake: How Much Protein You Really Need

Calculate your daily protein intake based on weight, activity and goal. Recommendations for muscle building, fat loss and maintenance — with food sources table.

2026-03-30·7 min

Calculate BMR: Basal Metabolic Rate With Two Formulas

Calculate your Basal Metabolic Rate (BMR) using Mifflin-St Jeor and Harris-Benedict formulas. Activity factors, influencing factors and practical tips.

2026-04-02·7 min

Calculate Calories Burned: How Many Calories You Really Burn

Calculate calories burned with MET values. Formula, activity table, influencing factors and tips to boost your burn.

2026-04-02·8 min

Intermittent Fasting Guide with Calculator

Intermittent fasting explained: protocols (16:8, 18:6, 20:4, OMAD), benefits, beginner tips, and free intermittent fasting calculator.

2026-04-02·8 min

VO2 Max Calculator: How Fit Are You Really?

Calculate your VO2 Max with the Cooper Test, Rockport Walk Test or direct entry. Fitness categories, age comparison and what your VO2 Max says about your health.

2026-04-02·7 min

Calculate One Rep Max: Estimate Your 1RM With Four Formulas

Calculate your one-rep max (1RM) using Epley, Brzycki, Lombardi and O'Conner formulas. Percentage chart and practical tips.

2026-04-02·7 min

Calculate Running Pace: Pace, Finish Time & Splits for Any Distance

Calculate your running pace for 5K, 10K, half marathon, and marathon. Pace in min/km and min/mi, finish time, negative split strategy, and km/mile splits.

2026-04-03·8 min

Period Calculator: Predict Your Next Period & Fertile Days

Understand your menstrual cycle: 4 phases, cycle length, irregularities and tracking benefits. Free period calculator included.

2026-04-03·8 min

Keto Calculator: How to Calculate Your Keto Macros

Calculate your keto macros — fat, protein and net carbs for the ketogenic diet. TDEE-based, personalized to your body and goals.

2026-04-03·8 min

Protein Requirements Calculator: How Much Protein Do You Really Need?

Calculate your daily protein requirement based on activity level, goal, and age. Recommendations for sedentary, athletes, weight loss, and muscle building.

2026-04-03·8 min

Blood Alcohol Calculator: How Long Until You're Sober?

Calculate your blood alcohol level with the Widmark formula. Alcohol elimination rate, influencing factors, legal limits and time until sober.

2026-04-08·7 min

Caffeine Calculator: How Long Until You Can Sleep?

Caffeine has a half-life of ~5 hours. Calculate your current caffeine level and find out when you can safely fall asleep tonight.

2026-04-08·7 min

Lean Body Mass Calculator — What It Tells You About Your Fitness

Calculate lean body mass using three scientific formulas: Boer, James and Hume. What LBM reveals about your fitness and why it matters more than body weight.

2026-04-09·8 min

Pregnancy Weight Gain Calculator — IOM 2009 Guidelines

How much weight should you gain during pregnancy? IOM 2009 recommendations by pre-pregnancy BMI, week-by-week breakdown, and twin pregnancies explained.

2026-04-12·7 min

Blood Sugar Converter — mg/dL to mmol/L Guide

Convert blood sugar between mg/dL and mmol/L. Understand fasting and postprandial reference ranges. Normal, Prediabetes, Diabetes explained with free calculator.

2026-04-13·8 min

GFR Calculator — Understanding eGFR & Kidney Function

Calculate eGFR using CKD-EPI 2021 and understand your kidney function. What do GFR values mean, CKD stages G1–G5, and when to see a doctor.

2026-04-12·8 min

Due Date Calculator: LMP, Conception & IVF Methods Explained

Calculate your due date from last period, conception date, or IVF transfer. Naegele's rule, gestational weeks, trimesters, and milestones explained.

2026-04-13·8 min

Child Growth Percentile Chart: What the Curves Really Mean

Growth percentile charts explained: how WHO curves work, what counts as normal and when to see a paediatrician.

2026-04-15·9 min

Life Expectancy Calculator — Factors That Really Matter

Calculate your life expectancy based on lifestyle, chronic conditions, and genetics. WHO 2022 country data with science-backed adjustment factors.

2026-04-15·8 min

Diabetes Risk Score: FINDRISC Explained

Calculate your type 2 diabetes risk with the FINDRISC score. How the test works, what the points mean, and which measures reduce your risk.

2026-04-18·9 min

Vitamin D Calculator: How Much Sun Do You Really Need?

How much sun for vitamin D? Skin type, latitude, season — all explained. With free vitamin D calculator.

2026-04-18·9 min

Alcohol Unit Calculator — Weekly Consumption & Health Risk

What is an alcohol unit? UK units, grams of pure alcohol, WHO risk categories and comparison with DHS, NHS and NIAAA guidelines explained.

2026-04-20·8 min

Body Temperature Calculator — Fever, Normal Range & Hypothermia

What is a normal body temperature? Learn about fever, hypothermia, temperature variation by site, and when to see a doctor. With free body temperature calculator.

2026-04-27·8 min

Anion Gap Calculator — Understanding Metabolic Acidosis

What is the anion gap? Formula, normal ranges, albumin correction, and MUDPILES explained. Free online anion gap calculator.

2026-04-27·8 min

Sodium Correction Calculator — Hyperglycemia and Pseudohyponatremia

Calculate corrected sodium in hyperglycemia using the Hillier formula. Recognize pseudohyponatremia, understand clinical significance, and review treatment.

2026-04-27·8 min

Biological Age Calculator — The Science Behind the Concept

Calculate your biological age based on resting heart rate, exercise, sleep, diet, and stress. PhenoAge-inspired algorithm explained with actionable tips.

2026-04-27·8 min

Body Type Calculator: Ectomorph, Mesomorph or Endomorph

Determine your somatotype using the Heath-Carter method. What do ectomorph, mesomorph and endomorph mean? Explained with training and nutrition recommendations.

2026-04-27·8 min

Body Surface Area Calculator — BSA Formulas and Medical Uses

Calculate body surface area (BSA) using Du Bois, Mosteller, Haycock, and Boyd formulas. Why BSA matters for chemotherapy dosing, burns, and kidney function.

2026-04-27·7 min

HbA1c Converter — Understanding Your Long-Term Blood Sugar

Convert HbA1c to estimated average glucose (eAG) and vice versa. Risk categories Normal, Prediabetes, Diabetes explained with formula.

2026-04-27·7 min

Smoking Cost Calculator: What Smoking Really Costs You

How much does smoking cost per year? With real examples, an investment comparison at 7% return, and motivation to quit.

2026-04-28·7 min

Child Dosage Calculator — Safe Weight-Based Paediatric Dosing

Calculate paracetamol, ibuprofen and amoxicillin doses for children by body weight. Formula, daily maxima and volume in mL.

2026-04-30·8 min

Cholesterol Ratio Explained: What Your Blood Work Really Tells You

Calculate your cholesterol ratios — Total/HDL, LDL/HDL and the atherogenic index. AHA/ESC risk classification, Friedewald formula and tips to improve.

2026-04-30·8 min

Prostate Cancer Risk: What Your PSA, Age and Family History Really Mean

Calculate your prostate cancer risk — PSA, age-adjusted thresholds and family history. Includes biopsy guidance per AUA / EAU recommendations.

2026-05-01·8 min

PCOS Symptom Checker: Rotterdam Criteria, Signs and the Path to Diagnosis

PCOS symptom checker — irregular cycles, hyperandrogenism, acanthosis nigricans and fertility issues. With Rotterdam criteria, diagnosis pathway and a free PCOS screener.

2026-05-01·8 min

Testosterone Level Calculator: Free vs Bound, SHBG and What Your Numbers Mean

Calculate free testosterone from total T, SHBG and albumin using the Vermeulen formula. Reference ranges, low-T symptoms, and natural ways to raise it.

2026-05-01·8 min

Erectile Dysfunction Test (IIEF-5): Score, Causes and What Works

Assess erectile dysfunction with the IIEF-5 (SHIM). Causes, severity bands by Cappelleri & Rosen, evidence-based interventions — anonymous and free.

2026-05-02·9 min

Male Pattern Baldness: Norwood-Hamilton Scale, Causes and Treatment

Assess male androgenetic alopecia with the Norwood-Hamilton scale. Stages, causes, minoxidil/finasteride and hair transplantation — evidence-based and free.

2026-05-02·9 min

Cardiovascular Risk Calculator: Framingham, SCORE2 and What the Numbers Mean

Estimate your 10-year risk of heart attack and stroke with Framingham/SCORE2. Cholesterol, blood pressure, lifestyle — and what actually moves the needle.

2026-05-03·9 min

Stroke Risk Calculator (CHA₂DS₂-VASc) for Atrial Fibrillation

Estimate stroke risk in atrial fibrillation with the CHA₂DS₂-VASc score. Risk factors, anticoagulation guidance per ESC guideline and tips to lower your risk.

2026-05-04·8 min

Blood Alcohol Estimator: Standard Drinks, BAC and Driving Limits

Estimate your blood alcohol concentration (BAC) fast using US standard drinks and body weight. Widmark formula, US/EU driving limits and hourly elimination — explained.

2026-05-05·9 min

Heart Failure Risk Calculator: Risk Factors, Symptoms and Prevention

Estimate your 10-year heart failure risk. Hypertension, CAD, diabetes, BMI — the biggest levers and what the evidence actually shows.

2026-05-04·8 min

Dehydration Risk Calculator: Spot Fluid Loss with Symptoms

Estimate dehydration risk from fluid intake, body weight, and symptoms. EFSA daily requirement, WHO/CDC symptom criteria, red-flag signs and rehydration guidance — explained.

2026-05-05·9 min

Thyroid Function Calculator: Read TSH, T3 and T4 Like a Pro

Interpret TSH, free T3 and free T4 values. Hypothyroidism, hyperthyroidism, subclinical patterns and what each marker really tells you.

2026-05-06·8 min

Anemia Risk Calculator: Spot Iron Deficiency and Low Hemoglobin Early

Screen for anemia from hemoglobin, sex, and 10 typical symptoms. WHO cutoffs, iron-deficiency clues, and treatment principles — explained.

2026-05-06·7 min

APGAR Score: How to Read 1- and 5-Minute Newborn Assessments

What the APGAR score at 1 and 5 minutes tells you about your newborn. The five criteria, scoring scale, normal vs. critical values — explained clearly.

2026-05-06·9 min

Osteoporosis Risk Calculator: Understand Your 10-Year FRAX Fracture Risk

FRAX-inspired estimate of your 10-year osteoporotic fracture risk. Risk factors, T-score, treatment thresholds, and prevention — clearly explained.

2026-05-07·7 min

Waist-to-Height Ratio (WHtR): Calculator, Risk & Ashwell Chart

Calculate your waist-to-height ratio (WHtR). Ashwell classification, measurement guide, and why WHtR outperforms BMI as a cardiometabolic risk marker.

2026-05-07·9 min

Hepatitis Risk Calculator: Screen for Hepatitis B and C from Exposure Factors

Estimate hepatitis B and C risk from 13 evidence-based exposure factors. Transmission routes, vaccination, post-exposure prophylaxis, and diagnostics — clearly explained.

2026-05-07·7 min

Corrected Calcium Calculator: Albumin Correction (Payne Formula)

Albumin-corrected calcium with the Payne formula — formula, normal ranges, hypoalbuminemia, and the limits of the correction. Free online calculator.

2026-05-07·8 min

Baby Feeding Amount Calculator: How Much Milk Does a Baby Need?

Calculate baby milk intake by age and weight. Evidence-based ml/kg guidance, amount per bottle, and practical signs of under- or overfeeding.

2026-05-07·8 min

Asthma Control Test (ACT) Guide: Score, Ranges, and Next Steps

How well is your asthma controlled? The validated 5-question ACT yields a 5–25 score with clear interpretation and step-up guidance for everyday management.

2026-05-07·9 min

COPD Assessment Guide: CAT, mMRC, and GOLD Group Explained

Quantify COPD symptom burden and exacerbation risk with mMRC, CAT, and GOLD 2023 ABE classification — score interpretation, thresholds, and treatment cues.

2026-05-07·9 min

Baby Milestones 0–24 Months — What Babies Do When

What developmental milestones should your baby reach at 2, 4, 6, 9, 12, 15, 18 and 24 months? CDC framework with watch-out signs and tips on when to call the pediatrician.

2026-05-08·8 min

Creatinine Clearance Calculator Guide: Cockcroft-Gault Explained

How to interpret your Cockcroft-Gault creatinine clearance: formula, normal ranges, CKD stages, drug-dosing role and how it relates to CKD-EPI eGFR.

2026-05-08·7 min

Pain Scale Guide — NRS, VAS, Wong-Baker Explained

How to use the NRS, VAS, and Wong-Baker FACES pain scales: when each is appropriate, what scores mean, and how to track pain over time.

2026-05-08·8 min

Newborn Jaundice: Bilirubin Risk Made Simple with the Bhutani Nomogram

How the Bhutani nomogram stratifies newborn bilirubin into risk zones. Hour-specific percentiles, risk factors, phototherapy thresholds — clearly explained.

2026-05-09·7 min

Steps to Calories & km: What 10,000 Steps Really Burn

How many calories does 10,000 steps burn? How far is that? Formula, activity levels and a quick reference table — in one guide.

2026-05-08·7 min

Child Calorie Needs: How Many Calories Does My Child Need?

How many calories does a child need per day? IOM EER formula, table by age and activity, growth, puberty — everything parents need to know.

2026-05-09·8 min

Pediatric Blood Pressure: Understanding the AAP 2017 Percentiles

How the AAP 2017 guideline classifies blood pressure in children — why age, sex, and height matter. Normal, elevated, stage 1 or stage 2 hypertension explained.

2026-05-09·11 min

Vitamin D Deficiency: Symptoms, Testing, How Much IU You Need

Vitamin D deficiency explained: symptoms, 25-OH-D blood test ranges in ng/mL, IU per kg dosing, D3 vs D2, food sources and the safety upper limit.

2026-05-10·7 min

Pregnancy BMI Calculator — Pre-Pregnancy BMI & IOM 2009

Calculate your pre-pregnancy BMI by WHO classification and see recommended weight gain by IOM 2009 — for singletons and twins. Why pre-pregnancy BMI matters most.

2026-05-10·8 min

Fertility Window Calculator: 10 Days, LH Surge & Peak Days

Calculate your fertility window — 10-day expanded window, LH surge, daily conception probability from Wilcox 1995. Practical tips for trying to conceive.

2026-05-11·8 min

Baby Head Circumference: Percentile Chart, Normal Range and When to See a Doctor

How to measure and interpret your baby’s head circumference. WHO percentile charts 0–36 months, normal range, microcephaly and macrocephaly explained.

2026-05-11·7 min

Breast Milk Alcohol: When Can I Breastfeed After Drinking?

How long alcohol stays in breast milk — Widmark formula, AAP guidance, per-drink clearance times, and a free calculator for nursing mothers.

2026-05-11·8 min

Menopause Symptom Calculator: MRS Score, Severity Bands and Treatment

Score menopause symptoms with the Menopause Rating Scale (MRS) — 11 items, 3 domains, Heinemann 2003 cutoffs. With calculator, severity bands and treatment overview.

2026-05-11·14 min

Prevent Type 2 Diabetes: 5 Evidence-Based Strategies

Prevent type 2 diabetes with 5 proven strategies: weight loss, exercise, low-GI diet, sleep, stress. Plus HbA1c, BMI and diabetes risk calculators.

2026-05-11·8 min

Pearl Index Calculator: Contraceptive Method Effectiveness

Pearl Index explained — formula, perfect vs typical use, reference values for the pill, condoms, IUDs, NFP. Sources: BZgA, Trussell.

2026-05-12·9 min

Iron Deficiency Calculator: Read Ferritin, TSAT and Symptoms Correctly

Screen for iron deficiency from ferritin, transferrin saturation, hemoglobin and 10 clinical signs. Cutoffs, latent deficiency, treatment, and diet — explained.

2026-05-13·8 min

FFMI Calculator: How to Read Your Fat-Free Mass Index

Calculate FFMI from weight, height and body fat. Normalized FFMI by Kouri, natural-athlete cutoffs, BMI comparison and training recommendations.

2026-05-13·8 min

Pregnancy Calorie Needs: How Many Calories per Trimester?

How many calories do you really need during pregnancy? Trimester table, IOM formula, the "eating for two" myth and practical tips for expecting mothers.

2026-05-13·14 min

Menopause — Natural Symptom Relief and When to See a Doctor

Menopause explained — perimenopause vs menopause, common symptoms, natural relief through diet, exercise, phytoestrogens, sleep and stress. Plus red flags, HRT overview and long-term bone and heart risks.

2026-05-13·9 min

Breast Cancer Risk Calculator: How the Gail Model Works

Calculate your breast cancer risk with the Gail model — 5-year and lifetime risk, key risk factors, screening thresholds and prevention options explained.

2026-05-13·8 min

PMS Symptom Calculator: PSST Score, PMDD Diagnosis and Treatment

Score PMS and PMDD with the Steiner PSST questionnaire. 14 symptoms, 5 functional impairment areas, evidence-based treatment guidance.

2026-05-26·7 min

Pediatric BMI Calculator: Understanding CDC Growth Percentiles

Pediatric BMI explained: why adult BMI cutoffs fail for children, how CDC growth-chart percentiles work, and when to see a pediatrician.

2026-05-27·7 min

Mean Arterial Pressure (MAP): Formula, Normal Range, Why It Matters

MAP explained: the (SBP + 2 × DBP) / 3 formula, normal ranges, why 65 mmHg is the critical floor, and what the target should be in older adults.

2026-05-28·7 min

HOMA-IR Calculator Guide: Spot Insulin Resistance Early

Calculate HOMA-IR from fasting glucose and fasting insulin. Formula, risk bands, what the index means and what to do about an elevated value.