Comparison

Opioids Dosage Conversion vs HAS

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Opioids Dosage Conversion

This app is a calculator for trained medical professionals to convert opioid analgesic dosages. It supports various common opioids and administration routes, offering features like breakthrough dosing and cross-tolerance calculations.

Highlights
  • Opioid dosage conversion
  • Multiple drug support
  • Multiple route support
  • Breakthrough dosing calculator
  • Incomplete cross tolerance option
  • Instructional details
Features
Read full description

Opioids by Chris Marcellino MD and Norris Vivatrat MD is an opioid analgesic dosage conversion calculator for use by trained medical professionals. The application supports conversion to and from opioids commonly prescribed and used in U.S. hospitals orally, parenterally, or transdermally, including morphine, codeine, hydromorphone, hydrocodone, fentanyl, methadone, oxycodone and oxymorphone. The application is intended to help and instruct in the process of conversion of opioid regimens. • Native support for iPhone, iPad and iPod touch • Multiple route support • Multiple drug support • Incomplete cross tolerance option • Breakthrough dosing calculator • Provides instructional details about each calculation • Saves last calculation on exit • Supports landscape and portrait modes • Reference guide By Professor EBM, the Internal Medicine Residency Teaching Resource for Evidence-Based Medicine: http://www.professorebm.com/, a resource of the Santa Clara Valley Medical Center. While effort has been made to ensure that calculations are accurate and that conversion factors are in accordance with current accepted medical practices, use of this application is entirely at your own risk. This application should only be used by trained medical professionals and all results should be double checked by hand. Use of the app requires acceptance of the terms of use that are included with the application. Please send support requests and feedback using the link in the About tab of the app, though as a free academic tool we only have limited resources to address new feature requests. Opioid equipotency data is taken from CAPC conversion values except where noted (see the reference tab in the app.) CAPC values are as published in the Center to Advance Palliative Care Prescribing Opioids: A Reference Guide curriculum, which are adapted from McPherson ML. Demystifying Opioid Conversion Calculations: A Guide for Effective Dosing, 2nd ed. American Society of Health-System Pharmacists, Bethesda, Maryland, 2018. EPEC values are as published in EPEC-O Participants Handbook, 2005. Chris Marcellino, MD — Mayo Clinic Norris Vivatrat, MD — UCSD Medical Center Special thanks to Dr. Tom Mouser (EveryStep, Des Moines, IA) and Dr. David Rand (UVM Medical Center).

About

HAS

Features
Read full description

HAS-BLED bleeding risk calculator. Base on the article in Chest. 2010;138(5):1093-1100. doi:10.1378/chest.10-0134. The calculator estimates one year risk of major bleeding when using warfarin in atrial fibrillation. SOG's calculator has been designed with ease of use and clarity in mind. All selections are made on a single page and you can see the risk score and risk assessment change as you switch the options.

Screenshots

Opioids Dosage Conversion4 screens
HAS1 screens

Verdict

The call

The clearest difference is price: Opioids Dosage Conversion at Free against HAS's $0.99. HAS's advantage is update cadence (every 3 weeks vs every 4 months) and iOS requirement (8.0 vs 15.6). On ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Opioids Dosage Conversion is free to download; HAS costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Opioids Dosage Conversion ships an update every 4 months, HAS every 3 weeks. The most recent releases landed on October 8, 2026 and October 6, 2026 respectively.

Scorecard3 real differences · 7 level
Opioids Dosage Conversion versus HAS: the parameters behind the verdict, then further details
ParameterOpioids Dosage ConversionHAS
PriceFree — better$0.99
Rating4.3 (18 ratings) — better—
Positive reviews77.8% of reviews—
Number of ratings18 — better—
Update frequencyEvery 4 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.68.0 — better
Further details — not scored
Size2 MB9 MB
Age rating17+17+
DeveloperChris Marcellino MD LLCTimo Strid

In-app purchases

None

Opioids Dosage Conversion

No in-app purchases

None

HAS

No in-app purchases

Questions

Is Opioids Dosage Conversion free?
Opioids Dosage Conversion is free to download, with no in-app purchases.
Is HAS free?
HAS costs $0.99, with no in-app purchases.
Do Opioids Dosage Conversion or HAS have ads?
Neither Opioids Dosage Conversion nor HAS shows ads.
Which is updated more often, Opioids Dosage Conversion or HAS?
Opioids Dosage Conversion ships an update every 4 months, and HAS every 3 weeks. Most recently, Opioids Dosage Conversion was updated on October 8, 2026 and HAS on October 6, 2026.

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