Editor’s note: MedCalc is no longer a free app in the App Store — we encourage you to try Calculate by QxMD to see if it fits your needs as a medical calculator before buying MedCalc. 

Here we review the MedCalc Pro app, developed by two Swiss doctors, Pascal Pfiffner, MD and Mathias Tschopp, MD, who share an interest in medical informatics and released the original MedCalc app last year. Pascal has also developed two other apps, KidneyCalc and Eponyms. For a full list of the formulas contained in the MedCalc Pro app, please scroll to the end of this review.

Of note, this Pro version (V2.0) is an upgrade on the free regular version of MedCalc (V1.2) that we reviewed in June 2009 and found superior to other paid medical calculators such as MediMath and Medical Calculator.

The primary differences between the regular and Pro versions are the patient management system and the presence of short descriptions or captions for each formula.

There are several additional formulas that have been included on this newer version (V2.0). The developers contemplated making some formulas available on the Pro version only, but ultimately decided to make all formulas available on both the regular and Pro versions. Also of note, MedCalc Pro is not yet available as an iPad-native application, but will soon be available as such with a free upgrade for those with MedCalc Pro on the iPhone/iPod touch.

As for the MedCalc Pro app itself, the home screen requires a click on the bottom bar to reach “All Formulas” (note how the formulas in this Pro version also contain a short caption describing the formula):

Another way to bring up a given formula is by searching for keywords. Here, for example, searching for “weight” brings up the BMI formula:

Formulas can be double-clicked to add them as “Favorites.” As I am on oncology night float, I have added the formulas I use most often on this rotation to my “Favorites” for easy access:

One useful feature on this app is that implausible inputs are highlighted in red (usually when a unit is set incorrectly), alerting the user to correct the unit:

Another nice touch is the ability to see bibliographic information with PubMed links for selected formulas. Here, for the universally-taught Light’s criteria for pleural effusions, clicking on the “I” or “Info” button on the top right brings up a quick summary of its clinical use as well as the associated bibliographic reference for the initial landmark article complete with PubMed link:

The patient management system (available only on the Pro version) allows for the saving and accessing of results for particular patients. In this manner, users can create a “patient database” through which they can save and browse formula results as well as autofill or preload formula fields with known data for these patients. This system can speed up data entry if the user is dealing with the same handful of patients over and over (as is sometimes the case for housestaff on inpatient rotations), but may not have very much utility otherwise.

In summary, the MedCalc Pro app represents a valuable resource on the wards. Particular strengths include the ability to search for formulas by keywords, a history of recent inputted values to speed up data entry, and formulas within formulas. Over the course of one oncology night float shift, I used this app to calculate the MELD score for a cirrhotic patient I admitted, to assess the FeNa for an inpatient who developed acute renal failure, to deduce the ANC for a febrile patient on chemotherapy, to figure out the retic index for an patient admitted with anemia, and (several times) to assist me with opioid pain management.

Pricing: The MedCalc Pro app costs $7.99 on iTunes, and the basic MedCalc app is free on iTunes.


-Support for both SI and US/Imperial units with easy switching on the keypad
-Customizable list for your most-often used formulas
-Bibliographic references with PubMed links for given formulas

Dislikes/Future Updates I’d Love to See:

-Though the patient management system can speed up data entry somewhat, it’s difficult to justify the $7.99 upgrade from the basic version to the Pro version, because the basic version works so well
-As with the earlier version, it takes an extra click after opening the app to reach the search bar for “All Formulas”


In our opinion, the MedCalc app represents an indispensable resource for the wards and clinic (as evidenced by the dozen times I pulled it out over my last night float shift) and is superior to the other medical calculators we have tried, but we find the basic free version sufficient for most of our activities.

MedCalc Pro iTunes Link

MedCalc Pro Website

• A-a O2 Gradient and Ratio
• ABCD2 Score
• Abbreviated Mental Test
• Absolute Neutrophil Count
• ADO Index
• Age
• Allowable Blood Loss
• Alvarado Score
• Anion Gap (serum)
• Anion Gap (urine)
• Aphasia Classification
• APGAR Score
• ASA Classification
• Basal Energy Expenditure
• Bicarbonate Deficit
• Bishop Score
• Blatchford Score
• BODE Index
• Body Mass Index
• Body Surface Area
• Burn Area
• Canadian C-Spine Rule
• Canadian CT Head Rule
• CAP PIRO Score
• Cardiac Output (echo)
• Cardiac Output (Fick)
• Cardiac Valve Area (Gorlin)
• CHADS2 Score
• Change In Serum Na
• Child-Pugh Classification
• Clin. Pulm. Infection Score
• Cormack Classification
• Corrected Ca (Albumin)
• Corrected Ca (Protein)
• Corr. Phenytoin (Albumin)
• Corrected Na (glucose)
• Corrected Na (lipids)
• Corrected Na (protein)
• Corticosteroids Equivalence
• CURB-65 Score
• CVC Optimal Positioning
• DAS28 (ESR and CRP)
• Delta Gap and Ratio
• Delta PP
• Dermatome Map
• Dose Calculator (w/ Calvert)
• Epworth Sleepiness Scale
• Eye Chart (Snellen)
• Expected PCO2 (Winters)
• Fisher Scale
• Fluid Repl. For Burns
• FOUR Score
• Fractional Excretion of Ca
• Fractional Excretion of Na
• Fractional Excretion of Urea
• Framingham Gen. CV Risk
• Geneva Score for PE
• GFR (Cockroft-Gault)
• GFR (Creatinine measured)
• GFR (Salazar)
• GFR (Schwartz)
• Glasgow EtOH Hep. Score
• Glasgow Coma Scale
• Glasgow Coma Scale (ped)
• Glasgow Outcome Scale
• Glasgow Scoring System
• Growth Velocity
• Harvey Bradshaw Index
• Heart Rate (EKG)
• Henderson-Hasselbalch
• Hepatitis Disc. Function
• Hunt Hess Scale
• Ideal Body Weight
• In-Flight PaO2
• Infusion Management
• Infusion: IV Drip Rate
• Infusion: Rule of six
• Injury Severity Score
• Interval Calculator
• Iron Deficit
• Karnofsky Scale
• Kt/V (URR)
• LDL Cholesterol
• Light’s Criteria
• Likelihood Ratios
• Liver Volume
• Lung Age
• Maintenance Fluid (children)
• Mallampati Classification
• Mean Arterial Pressure
• MELD (-Na) Score
• Microalbuminuria
• Molarity
• NAC Dosage Regimen
• NACA Scale
• Number Needed To Treat
• NYHA Functional Class.
• Odds – Probability Conv.
• Opioids Equivalence
• Osmotic Gap (serum)
• Osmotic Gap (stool)
• Oxygen Index
• O2 Tank Remaining Time
• O2 Transport Parameters
• Pain Visual Scale
• PaO2 / FiO2 Ratio
• Pediatric Trauma Score
• Pediatric Tube Size
• PELD Score
• Plasma Volume
• Pneumonia Severity Index
• Post-test Probability (LR)
• Post-test Probability (Sn/Sp)
• Pred. Body Weight (ARDS)
• Pred. Peak Flow (adults)
• Pregnancy Wheel
• Pressure Gradient
• Protein Excretion
• Q-Tc
• Ramsay Sedation Scale
• Rankin Scale (Modified)
• Ranson’s Score
• Red Blood Cell Indices
• Resuscitation Doses (ped)
• Reticulocyte Index
• Revised Trauma Score
• Richmond Agit. Sed. Scale
• Rockall Score
• San Francisco Syncope Rule
• Sedation-Agitation Scale
• Serum-Ascites Alb. Grad.
• SOFA Score
• Solitary Nodule Risk
• Spirometric Values
• Target Height
• TASH Score
• Teeth Numbering (FDI/Univ.)
• TIMI Scores
• Transferrin Saturation
• Transtubular K Gradient
• Tubular PO4 Reabsorption
• Two-Way Table
• Units Conversion (physics)
• Units Conversion (chem.)
• Urinary Excretion of Calcium
• Urine Output
• VAP PIRO Score
• Vascular Resistances
• Warfarin Dosage Nomogram
• Water Deficit
• Wells Score for DVT
• Wells Score for PE
• WFNS for SAH