iPhone Screenshots


RapidCalc is proudly supported by GlucoMen in UK and Ireland.

RapidCalc is a sophisticated bolus insulin dose calculator for diabetics following a basal-bolus regimen. With intelligent tracking of insulin on board, automatic carbohydrate ratio and blood glucose target selection, RapidCalc dramatically simplifies blood glucose management. Complete with detailed history, charting and statistics features, RapidCalc is designed to be easy to use and easy to live with.

Can't remember when or how much you last dosed? - Don't worry. RapidCalc avoids dose stacking by keeping track of your bolus doses and factoring in Insulin On Board when calculating a suggested dose.

RapidCalc supports up to 6 different target blood glucose levels, correction factors and carbohydrate ratios for different times of day and automatically selects the appropriate values when calculating a suggested dose.

Unique slide-and-tap controls let you enter your blood glucose and carbohydrate values quickly and easily. Simply drag the slider close to your value and then tap on the slider rail to make fine adjustments. As you adjust your values RapidCalc instantly recalculates suggested meal and correction bolus doses.

RapidCalc also makes it easy to record your background insulin doses and supports up to three preset doses with optional reminders.

RapidCalc delivers many of the benefits normally associated with an insulin pump and indeed users describe it as being like "pumping without a pump". With RapidCalc it is possible to achieve control similar to that of a well set up pump.

Integrated dose adjustment for exercise based on intensity and duration as well as compensation for recent hypos or alcohol.

RapidCalc effectively replaces your log book, providing a full 90-day history of blood glucose readings, insulin doses and carbohydrate intake which can be exported via email for archive or analysis. Built-in charts and summary statistics help you assess your blood glucose control, identify trends and even estimate your HbA1c.

> Intelligent tracking of Insulin On Board
> Suggested insulin dose based on blood glucose, carbs and insulin on-board
> Automatic target pre-meal blood glucose level selection
> Automatic correction factor and carb ratio selection
> Unique slide-and-tap input for quick data entry
> Basal dose recording with with presets and reminders
> Dose adjustment for exercise intensity and duration
> Clear, interactive controls with instant dose feedback
> Charting of blood glucose readings and trend data
> Pre and post meal BG comparisons
> Summary statistics for doses, glucose and carbohydrates
> Estimated HbA1c based on average readings
> 90-day rolling history
> Backup/Export history data and settings via email
> Integrated safety warnings and guidance
> Choice of mmol/L or mg/dL blood glucose units
> Enter Carbs in grams or portions of 10, 12 or 15g
> Choice of % or mmol/mol HbA1c units
> Customised carb ratios and correction factors
> Customised target, warning and ideal glucose levels
> Password protected settings for pediatric use
> No Wifi or 3G connection needed
> Built-in help

RapidCalc is intended for guidance only and is not a substitute for professional medical advice. Always discuss use of the calculator with your health care professional and only use personal settings agreed with them. If you are in any doubt as to the correct insulin dose always follow the advice of your healthcare professional.

What’s New

Version 2.1.6

Changes in this version:
- Fixed display bug in settings

Ratings and Reviews

4.3 out of 5
12 Ratings

12 Ratings

Oliverjp ,

Very useful app

Brilliant app as it allows you to take proper control over your insulin requirements. With a little bit of practice this app will get your HbA1c down and just as important, will also flatten your blood glucose curve considerably.

Two downsides. First is setup. It needs parameters setting that are at least approximately correct to get you started. With a bit of understanding and a couple of days tweaking I am sure most reasonably aware users could get it purring. If not, get your diabetic nurse to help - just don't bother asking an old-fashioned one that doesn't believe in patients taking control of their treatment!

Only other downside is there are still some peculiarities in the software. The worst is that if you cannot get it to record an insulin shot of over 50 units RAI, so all you highly insulin resistant folks be aware. It is still useable, but a settable parameter to allow RAI recording over 50 units would be really helpful - developers please note! On an iPhone you also can't properly see any bolus shot over 99 units. For example, a shot of 225 units shows as 22.. but records OK

Overall, a blindingly useful app and the best diabetes app I have used.

diabeetgeek ,

Best insulin calculator app

I’ve been using this app since I completed the DAFNE course in 2018, as my maths skills are beyond rubbish. This app is amazing, it tells you how much insulin your due, does all the calculations, corrections, what the BG is , and it estimates your HbA1C. My only glitch with the app is that sometimes it “crashes” in that when I open it I can’t get access to the screen as its half covered with the exercise fields. The only way I can then use the app is to restart my iPad.

Developer Response ,

Thanks for taking the time to leave feedback. We are delighted that you are finding RapidCalc so helpful. We have had a couple of reports of the App freezing under iPad OS 13. The problem appears to be very intermittent and we are still trying to establish the exact cause. One user has reported that RapidCalc does recover when the browser cache was cleared. Whilst we have never had any problems running RapidCalc on the iPad in the past, the App was specifically designed for the iPhone. If you have that option it might be worth running RapidCalc on an iPhone rather than your iPad

Guillianos family ,

Excellent app

I was diagnosed 6 weeks ago and this app has made my life so easy. My sugars are regulated and the app allows me to store all my info including pics of what I eat which helps


Gilport Enterprises Pty Ltd
5.3 MB

Requires iOS 6.0 or later. Compatible with iPhone, iPad and iPod touch.


English, Dutch, Italian, Spanish

Age Rating
Infrequent/Mild Medical/Treatment Information


  • Family Sharing

    Up to six family members will be able to use this app with Family Sharing enabled.

You May Also Like