MDTools.org provides free, evidence-based clinical calculators and medical reference tools for healthcare professionals. No sign-up required, no ads, no paywalls.
- Cardiology: CHA₂DS₂-VASc, HEART Score, TIMI Risk, HAS-BLED, QTc Calculator
- Nephrology: eGFR (CKD-EPI), Creatinine Clearance, FENa, Free Water Deficit
- Pulmonology: A-a Gradient, CURB-65, Wells Score (PE & DVT)
- Hepatology: MELD Score, Child-Pugh, FIB-4
- Neurology: NIH Stroke Scale (NIHSS), Glasgow Coma Scale, Canadian CT Head Rule
- Emergency: SOFA Score, qSOFA, APACHE II, Parkland Formula
- Endocrinology: A1C Converter, Corrected Calcium, Thyroid Dosing
- Hematology: Absolute Neutrophil Count, Corrected Reticulocyte Count
- Psychiatry: PHQ-9, GAD-7
- Pediatrics: Pediatric GCS, Weight-Based Dosing, Infant Acetaminophen & Ibuprofen Dosing
- Pharmacy: Day Supply, Prescription Refill, Medication Timing
- Drug Dosing: Vancomycin AUC, Heparin, Warfarin, Insulin, Ketamine, Lidocaine
- Nutrition: BMI, Reverse BMI, TDEE, BSA, Body Fat, Calorie Calculator
- OB/GYN: Gestational Age, Due Date
- Comprehensive normal ranges by age and sex
- Includes: Sodium, Potassium, Creatinine, BUN, Calcium, Albumin, CRP, BNP, Bilirubin, ALP, Chloride
- Grounded in peer-reviewed sources (Tietz Textbook, NEJM, KDIGO, AHA)
- ✅ 100% Free — No accounts, no paywalls, no ads
- ✅ Evidence-Based — Formulas verified against published medical literature
- ✅ Mobile-Friendly — Responsive design works on any device
- ✅ Fast — Static site, loads instantly
- ✅ Multilingual — Available in English and German
- ✅ No Tracking — Privacy-first, minimal analytics
- ✅ Structured Data — Schema.org markup for rich search results
- Website: https://mdtools.org
- German Version: https://mdtools.org/de/
| Calculator | Description | Link |
|---|---|---|
| BMI Calculator | Body Mass Index with WHO categories | Open |
| eGFR Calculator | CKD-EPI 2021 equation | Open |
| A1C Calculator | A1C ↔ Average Glucose converter | Open |
| CHA₂DS₂-VASc | Stroke risk in atrial fibrillation | Open |
| Corrected Calcium | Albumin-adjusted calcium | Open |
| Glasgow Coma Scale | Consciousness assessment | Open |
| Creatinine Clearance | Cockcroft-Gault equation | Open |
| MELD Score | Liver disease severity | Open |
| Anion Gap | Metabolic acidosis workup | Open |
| QTc Calculator | Corrected QT interval | Open |
- Pure HTML/CSS/JavaScript — no frameworks, no build step
- Hosted on Cloudflare Pages (edge-delivered globally)
- Schema.org structured data (MedicalWebPage, FAQPage, BreadcrumbList)
- Automated sitemap generation
MDTools calculators are intended for use by healthcare professionals as clinical decision support tools. They are not a substitute for professional medical judgment. Always verify calculations and consider the full clinical picture before making treatment decisions.
Found an error in a formula? Have a suggestion for a new calculator? Please open an issue or submit a pull request.
MIT License — see LICENSE for details.
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