Health & Medical calculators

259 live health & medical tools on The Online Calculator 24, grouped into 5 sub-topics — body measurements, nutrition, fitness performance, clinical calculators, medications & dosing. Each one publishes the formula it uses, works the arithmetic step by step from its own starting figures, and names the standard, regulation or dataset the math traces back to, so you can check an answer instead of trusting it.

Sub-topics inside Health & Medical

• Body Measurements — 51 live calculators.
• Nutrition — 51 live calculators.
• Fitness Performance — 54 live calculators.
• Clinical Calculators — 53 live calculators.
• Medications & Dosing — 50 live calculators.

A sample of what is live

• BMI Calculator — Check your Body Mass Index with the WHO formula and see the weight ranges that apply to your height.
• Muscle Mass Estimate Calculator — The share one quantity represents of another — the core reading behind muscle mass estimate — with a second value folded in for direct comparison.
• Hip Circumference Calculator — Tape-meat body composition for hip circumference: the US Navy circumference method — the field standard gyms and physicals actually use — with fat and lean mass in kilograms.
• Body Frame Size Calculator — A transparent linear conversion for body frame size: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• BMI Percentile (Children) Calculator — The share one quantity represents of another — the core reading behind bmi percentile (children) — with a second value folded in for direct comparison.
• Sitting Height Calculator — The share one quantity represents of another — the core reading behind sitting height — with a second value folded in for direct comparison.
• Calorie Needs Calculator — Estimate your daily calorie needs (TDEE) for maintenance, weight loss or muscle gain, based on Mifflin-St Jeor BMR and your activity level.
• Weight Loss Rate Calculator — The calendar answer behind weight loss rate: at your chosen daily balance, the pounds move on this date — using the 7,700-kcal-per-kg energy equivalent.
• Sodium Limit Calculator — A transparent linear conversion for sodium limit: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Cholesterol Limit Calculator — A transparent linear conversion for cholesterol limit: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• PRAL Score Calculator — Attainment of pral score against a target, with the absolute gap and the weighted contribution for scorecard roll-ups.
• MIND Diet Score Calculator — The plain odds behind mind diet score: single-event probability, the fair-price payout it implies, and how repetition moves the chance of at least one success.
• VO2 Max Calculator — Estimate your VO2 max — the gold-standard measure of cardiorespiratory fitness — from resting and maximum heart rate.
• Heart Rate Zone 4 Calculator — The 80–90% threshold zone: intervals and tempo efforts that train lactate clearance itself, the highest-yield band for race pace.
• Running Power Calculator — The mechanical power a runner produces, built from the di Prampero model: metabolic cost, vertical work on grades, and air drag.
• CrossFit Benchmark Calculator — How far a CrossFit benchmark workout landed from prescription — completed reps (scaled half-credited) against the Rx rep target, with intensity as load·reps per minute.
• Balance Score Calculator — Attainment of balance score against a target, with the absolute gap and the weighted contribution for scorecard roll-ups.
• Anaerobic Capacity Calculator — Attainment of anaerobic capacity against a target, with the absolute gap and the weighted contribution for scorecard roll-ups.
• Glasgow Coma Scale (GCS) & Acute Neurological Assessment Calculator — Calculate acute neurological impairment and traumatic brain injury (TBI) severity using the gold-standard Glasgow Coma Scale (GCS 3–15).
• Osmolality Calculator — Estimates serum osmolality from routine panel values — the tonicity workhorse of hyponatremia and toxic-ingestion assessment.
• LDL Martin/Hopkins Calculator — Replaces Friedewald’s fixed TG/5 with an individualized VLDL-to-TG ratio from percentile data — CDC-standardized and validated in NHANES.
• CHA2DS2-VASc Calculator — The share one quantity represents of another — the core reading behind cha2ds2-vasc — with a second value folded in for direct comparison.
• PURSUIT Score Calculator — Attainment of pursuit score against a target, with the absolute gap and the weighted contribution for scorecard roll-ups.
• PSI PORT Score Calculator — Attainment of psi port score against a target, with the absolute gap and the weighted contribution for scorecard roll-ups.
• Weight-Based Dose & Liquid Concentration Calculator — Calculate accurate pediatric and adult weight-based medication doses (mg/kg/day), dosing frequency splits (q6h, q8h, q12h), and liquid suspension volume in mL.
• Oral Bioavailability Calculator — The fraction of an oral dose that reaches circulation intact — AUC ratio corrected for the two doses, absorbing gut and first-pass liver into one number.
• Peak and Trough Calculator — The plateau band a multiple-dose regimen lives in: steady-state peak and trough from the IV-bolus superposition model.
• Vancomycin Dose Calculator — The 2020 ASHP/IDSA vancomycin guidance as arithmetic: mg/kg of actual weight, interval by renal function, and an AUC/MIC target replacing trough-only monitoring.
• Metformin Dose Calculator — The renal-function dosing ladder for metformin: eGFR bands set the maximum, and the bands are the current FDA/EMA relabeling, not the old creatinine folklore.
• Morphine Equivalent Calculator — The sum of every opioid a patient takes scaled to morphine equivalents — the single number behind prescribing-monitoring-programme risk rules.

How the Health & Medical engines are built

Three things hold every tool in this category together. The calculation is a real formula rather than a lookup of someone else's rounded answer, so unusual inputs behave sensibly. The result comes with interpretation — verdict bands, the gap against a target, or the range a reasonable change in assumptions moves it. And the guide on each page is generated from that engine's own numbers, which is why two adjacent tools in the same sub-topic do not hand you the same paragraph with a different noun pasted in.

Where this sits in the library

Health & Medical is one of 21 categories among the 3,602 engines The Online Calculator 24 serves today. The full index is at all categories, and the General workbench covers ROI, payback, margin, break-even and cost-per-unit for figures that do not fit a dedicated tool.