# UnitConverter Pro > Sophisticated unit converter for iOS with extensive unit support and a user-friendly interface. (iPhone/iPad app by Motohiro 大森.) - Source: https://appshunter.io/ios/app/unitconverter-pro/id311325306 (this page in markdown: same URL + `.md`) - Developer: [Motohiro 大森](https://appshunter.io/developer/311325309) - Category: Utilities, Productivity - Price: $0.99 - Rating: 4.20/5 from 5 App Store ratings · 13 written reviews indexed - Age rating: 4+ - Requires: iOS 10.0 · 3 MB - Languages: American English, Japanese - Released: 2009-06-06 - Data updated: 2026-06-10 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/unitconverter-pro/id311325306/reviews.md ## What is UnitConverter Pro? "UnitConverter Pro" is the best and most sophisticated unit converter for iOS. It covers 649 units from 56 categories used by various users from students to engineers in their daily life or scientific/engineering calculation. Multiple units like feet + inch are also supported. ◆◆ Simple and Speedy User Interface ◆◆ Only two taps to get a required unit conversion table! (1) Tap desired unit category in category list and (2) tap value field of any unit you want to convert from. Immediately, converted values are displayed for all the other units based on "1.0" of the unit you tapped. When you want to input arbitrary figure, tap the value field one more time to display a numerical keypad, which is specialized for input numbers including exponential expression. ◆◆ Functional digital display ◆◆ Converted values are rounded with user-specified decimal place and delimiting every three digits with comma. You can change decimal place from 1st to 9th any time. ◆◆ Search for a unit ◆◆ Copy & paste unknown units as well as numbers you find in internet or papers. UnitConverter Pro searches the unit from all the implemented units and show you a converted value immediately. ◆◆ Copy and Paste ◆◆ Double tapping a unit label allows you to copy converted value or to input figure by paste. ◆◆ "Favorites" category ◆◆ You can create your custom page in "Favorites" category by registering any units from any categories. ◆◆ Customization of category and unit list ◆◆ User preference screen allows you to customize the category list as well as unit list by eliminating unnecessary categories and units. ◆◆ Optional selection for Calorie/BTU definition ◆◆ There exists several definition commonly used for Calorie/BTU calculation. User preference screen allows you to specify the definition used in the conversion from the following list: - Thermochemical Calorie - International Table Calorie (14.5℃ Calorie) - 15℃ Calorie == Category List for Ver.2.3 == ◆ Lengh-related : Length / Area / Volume / Velocity / Acceleration / Diffusion Coefficient / Volume Flow Rate / Specific Fuel Consumption ◆ Mass-related : Weight / Mass Flow Rate / Density / Specific Volume / Mass Velocity / API Gravity ◆ Power-related : Power / Surface Tension / Pressure / Viscosity / Kinetic Viscosity ◆ Heat/Energy-related : Energy / Power / Heat Flow / Heat Flux/ Heat Relieving Rate / Specific Enthalpy / Mol. Specific Enthalpy / Specific Heat / Mol. Specific Heat / Thermal Conductivity / Heat Transfer Rate / Fouling Resistance / Torque / Gas Calorific Value ◆ Light-related : Luminance / Illuminance / Luminous Flux ◆ Electromagnetic-related : Magnetic Flux / Magnetic Flux Density / Radioactivity / Exposure Dose / Electric Current / Electric Charge / Voltage / Electric Resistance / Electric Conductivity / Electrostatic Capacitance ◆ Others : Time / Temperature / Angle / Molecular Number / Mole Flow Rate / Mol. Concentration / Blood Sugar Level / Spectroscopy / Concentration / Data Size / Data Rate ## Key features - 649 units from 56 categories - Simple and speedy user interface - Functional digital display with rounding - Search for units - Copy and paste functionality - Favorites category for custom pages - Customizable category and unit lists ## Recent user reviews (10 of 13) All indexed reviews: https://appshunter.io/ios/app/unitconverter-pro/id311325306/reviews.md ### 5/5 — Best unit convert app *2022-04-20* I looked through a lot of unit convert apps. This is the best by far. I’ve been using this for about a decade. Nothing better out there. ### 3/5 — Brilliant..... until iOS 14.2 *2020-11-09* This App was brilliant, until I updated to iOS 14.2, now it won’t open. I am lost without it. ### 5/5 — Perfect *2019-12-08* Excellent app; thorough and very easy to use. Love the way clicking the value initially imputes a 1. More helpful than one would at first realize. ### 5/5 — Excellent *2012-04-15* The best conversion app by far. ### 1/5 — Good *2011-07-16* Good ### 5/5 — excellent for serious engineering-science users *2010-12-11* This app has a huge variety of dimensions of measurements, and within each a large variety of units of measurement. The user interface is the best I've seen amongst the unit conversion programs, being both eminently usable and very attractive. Many unit converters suffer from awkwardness in switching from selecting dimensions of measurement to units of measurement, but such is not the case here - very easy and intuitive, plus the number of places shown is easily user-selectable. I haven't come across any errors. Looking at the organization of the units of measurement, the author appears to think first in SI units, then in imperial (UK) units, and lastly in US units, but as a US user I don't find much lacking other than obsolete units of measure from agricultural commerce (and if you're buying peaches by the bushel, you already know how much a bushel is). This is definitely the class act among unit converters for serious users, and is well worth 99 cents - kudos to the author. For the everyday user not needing this app's variety of units, I think Measures Lite is the best amongst the free unit converters. ### 5/5 — Includes Torque conversion! *2010-10-26* Very handy for the auto. enthusiast with old tools (like me!). Nice to be able to convert Nm and kgm to ft/lbs quickly on the job! Edit Excellent customer service with a recent enquiry. ### 1/5 — Upgrade turned great to crap *2010-08-04* This ap was the greatest converter I ever used. The upgrade makes you're enter every unit in every category. The developer says, "sorry for the inconvenience." Do not buy until the downgrade is reversed. ### 5/5 — True professional app *2010-06-22* Took me a while to find this one. Clean, comprehensive & quick. ### 5/5 — Excellent App *2010-03-06* More conversions than any other Unit Converter on App. Strongly recommended for anyone who wants a Unit Converter. Definitley worth more than what it is being sold for. Don't expect currency conversion in Unit Converter Pro. This is exclusively for Unit Conversions only, not Currencies. ## Frequently asked questions about UnitConverter Pro ### What is UnitConverter Pro? UnitConverter Pro is a sophisticated unit conversion application for iOS devices. It supports a vast number of units across many categories, making it useful for students, engineers, and general users. ### How many units and categories does UnitConverter Pro support? UnitConverter Pro supports 649 units from 56 different categories, offering comprehensive conversion capabilities for a wide range of needs. ### Is UnitConverter Pro easy to use? Yes, UnitConverter Pro is designed with a simple and speedy user interface. Conversions can often be completed in just two taps, and it includes a specialized numerical keypad for easy input. ### Can I customize UnitConverter Pro? Yes, you can customize UnitConverter Pro by creating a 'Favorites' category for frequently used units and by eliminating unnecessary categories and units from the lists in the user preference screen. ### What is the price of UnitConverter Pro? UnitConverter Pro is a paid application, priced at $0.99. There are no in-app purchases or advertisements. ### Does UnitConverter Pro have ads? No, UnitConverter Pro does not contain advertisements. It is a paid application designed to be ad-free for a seamless user experience. ### What devices is UnitConverter Pro compatible with? UnitConverter Pro is compatible with iPhone and iPod devices. It is available for iOS. ### How often is UnitConverter Pro updated? The latest version of UnitConverter Pro is 2.9, last updated on October 9, 2017. While not frequently updated recently, it offers a stable set of features. ## Version history (last 5 releases) ### 2.9 — 2017-10-09 This app has been updated by Apple to display the Apple Watch app icon. Updated for iOS11 Newly added user-defind unit category for units which are not in the list. ### 2.4 — 2011-01-12 Bug fixed for some categories (pressure, data rate, etc.) crashing in iOS4.2. Added New button, "select all" and "deselect all", for unit setting. New category "Mass-energy equivalence (E=mc2)" Several new units for "Specific fuel consumption", "Force" and "Torque". ### 2.3.2 — 2010-11-02 Fixed bug for some Japanese length units ### 2.3.1 — 2010-10-28 Added 77 new units including 2 new categories. New "quick input mode" to get numerical keypad with a single tapping. Improved search function. ### 2.3 — 2010-07-22 Added 7 new category (Electric current / Electric charge / Voltage / Electric resistance / Electric conductivity / Electrostatic capacitance / Gas calorific value) and several new units. Direct conversion from numbers and units typed in search bar. Mail for your comments and requests. several bug fixes ## Apps similar to UnitConverter Pro | App | Rating | Price | Category | | --- | --- | --- | --- | | [D4H Personnel & Training](https://appshunter.io/ios/app/d4h-personnel-and-training/id1456365440) | 3.0 (11) | Free | Utilities | | [Siemens Healthineers Events](https://appshunter.io/ios/app/siemens-healthineers-events/id1462867980) | — | Free | Utilities | | [Veronique](https://appshunter.io/ios/app/veronique/id1459914360) | — | Free | Utilities | | [CalcuLatte](https://appshunter.io/ios/app/calculatte/id1464511080) | — | Free | Utilities | | [晓语听听](https://appshunter.io/ios/app/id1462853240) | — | Free | Utilities | | [NovaTec - Diário de Obras](https://appshunter.io/ios/app/novatec-diario-de-obras/id1460271080) | — | Free | Utilities | --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-10.*