Comparison

Units vs Unit Converter

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

Head to head
About

Units

Easily convert between hundreds of units across 43 categories, including currency with daily updated rates. Customize your workflow by hiding or reordering units and categories.

Highlights
  • Hundreds of units across 43 categories
  • Daily updated currency exchange rates
  • Hide unused units
  • Reorder units and categories
  • Universal app support (iPhone, iPod touch, iPad)
Features
Read full description

Units is the fast, friendly unit converter. Type a number into any unit and instantly see it in every other one, all on a single screen. There's no picking what to convert from and to, no digging through menus, and no ads. With more than 800 units across 43 categories, Units covers everyday conversions like length, weight, volume and temperature, and the ones you need less often, from torque and fuel consumption to data rates, shoe sizes and musical notes. SEE EVERYTHING AT ONCE • Enter a value in any unit and every other unit in the category updates as you type • A keypad made for numbers, so the decimal point is always right where you need it CURRENCY • Convert between more than 160 currencies • Exchange rates updated every day MAKE IT YOURS • Hide the units you never use, so the ones you need are always in view • Reorder units and categories so your favorites come first • Switch on a two-column layout to see even more at a glance • Leave a tip to unlock a collection of alternative app icons MADE FOR YOUR DEVICES • Designed for iPhone and iPad, with your categories and conversion side by side on larger screens • Makes full use of iPhone Duo, whether it's open or closed • Handoff picks up a conversion where you left off on another device • Supports Dark Mode and Dynamic Type Units has been converting since 2008, and is lovingly made in Scotland.

About

Unit Converter

This app offers a comprehensive unit conversion tool with over 300 units across 27 categories. It supports compound units, date calculations, and conversions between various number systems, including historical units. The interface is designed for ease of use with smart keyboards and customizable display options.

Highlights
  • 27 conversion categories
  • 300+ units
  • Compound unit support
  • Date calculator
  • Fractions and number conversions
  • Historical units
  • Customizable interface
Features
Read full description

Convert everything - 31 categories, 300+ units! Mila's Tools Unit Converter puts 31 converters in your pocket at no cost. Whether you need to convert temperatures for a recipe, check tire pressure in PSI, find your ring size across international standards, or calculate the days until a deadline, this app handles it all with precision and ease. What customers are saying: ***** "Get it! Nothing better than this!" ***** "This is the best quick ref tool I have come across to date" ***** "Undoubtedly the best conversion app in the App Store." ***** "Best app for me so far." ***** "Intuitive interface. The app design is so easy you'll actually use it." 31 CONVERSION CATEGORIES Angle · Area · Bits & Bytes · Blood Sugar · Capacitance · Cooking · Current · Data Transfer Rates · Dates · Density · Energy · Flow Rate · Force · Fractions · Frequency · Fuel Economy · Gauges · Illuminance · Length · Numbers · Power · Pressure · Ring Sizes · Shoes · Slope · Speed · Temperature · Time · Torque · Volume · Weight COMPOUND UNITS Work with real-world measurements like feet + inches, pounds + ounces, or gallons + quarts. Values auto-normalize — type 13 inches and see 1 foot 1 inch instantly. DATE CALCULATOR Find the exact number of days, weeks, months, and years between any two dates. Add or subtract time from a date with quick-action shortcuts like "90 Days from Today" or "End of Year." DATE CONVERTER See any date across 10 calendar systems — Gregorian, Islamic, Hebrew, Chinese, Persian, Indian National, Coptic, Ethiopic, Buddhist, and Japanese — plus Unix timestamps, Julian Day numbers, and ISO 8601 week dates. Tap the info icon for details on each calendar system. FRACTIONS & NUMBERS Convert between fractions, decimals, and percentages. Translate numbers into Roman numerals, binary, octal, and hexadecimal. Explore magnitudes from thousands to decillions. RING SIZES Convert between US, EU, Swiss, Japanese, Chinese (Mainland), and Hong Kong ring sizing standards. View inner diameter and circumference in millimeters for precise measurements. HISTORICAL UNITS Go beyond modern measurements with ancient Egyptian, Mesopotamian, Greek, Roman, and Biblical units of length. BUILT FOR PRECISION Choose automatic smart formatting or set manual decimal precision from 0 to 10 places. Locale-aware number formatting respects your region's separators and conventions. SMART CUSTOM KEYBOARDS Purpose-built keyboards for every input type — numeric, whole number, Roman numeral, binary, octal, and hexadecimal — so you never have to fight autocorrect. DESIGNED FOR YOU • Dark mode with rich, category-specific color themes • Comfortable or compact view styles • Show or hide any unit in any category • Available on iPhone, iPad, and Mac Download now and experience the most comprehensive unit conversion app available! - - - - - Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Units4 screens
Unit Converter4 screens

Verdict

The call

The clearest difference is rating: Unit Converter at 4.8 against Units's 4.1. Unit Converter also leads on review sentiment (88% vs 60%) and update cadence (weekly vs monthly). On price, ads, in-app purchases and monetization model 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

Both are free to download. Units sells 3 one-off in-app purchases and Unit Converter sells 3 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Unit Converter holds the better App Store score, 4.8 against 4.1. That said, the two scores are not equally well evidenced: Unit Converter has 1.5K ratings behind it against 51, so its average is the more settled of the two. Written reviews point the same way: 60% of Units's written reviews are positive against 88% of Unit Converter's.

UpkeepUpdate frequency

Units ships an update monthly, Unit Converter weekly. Both last shipped on November 6, 2026.

Scorecard4 real differences · 6 level
Units versus Unit Converter: the parameters behind the verdict, then further details
ParameterUnitsUnit Converter
PriceFreeFree
Rating4.1 (51 ratings)4.8 (1.5K ratings) — better
Positive reviews60.1% of reviews87.7% of reviews — better
Number of ratings511.5K — better
Update frequencyMonthlyWeekly — better
AdsYesYes
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad
Requires iOS17.0 — better17.6
Further details — not scored
Size86 MB13 MB
Age rating4+4+
DeveloperHomegrown Software LtdScott DeSapio

Customer experience

Units

All ratings49 ratings
Positive79.6%
Neutral4.1%
Negative16.3%
Written reviews581 reviews
Positive60.1%
Neutral12.0%
Negative27.9%

Unit Converter

All ratings1,485 ratings
Positive95.2%
Neutral1.0%
Negative3.8%
Written reviews365 reviews
Positive87.7%
Neutral3.0%
Negative9.3%

User reviews

Units

From 51 App Store ratings

What we love

  • 🚀 Efficient and fast conversions
  • 👍 Comprehensive list of units
  • 🔍 Customizable unit selection
  • 💰 Free app with optional paid version
  • 🔧 Useful for engineering and technical work

Room to improve

  • 🐛 Crashes and stability issues
  • 🕰️ Outdated currency conversion rates
  • 🔍 Too many unit categories, hard to navigate
  • 💰 Ads in free version
  • 📏 Ruler feature not accurate on some devices

Unit Converter

From 1.5K App Store ratings

What we love

  • 👍 Easy to use
  • 🚀 Quick and accurate conversions
  • 💡 Comprehensive list of units
  • 🔍 Convenient for everyday use
  • ⭐ Reliable and consistent

Room to improve

  • 🐛 Scrolling issues on newer devices
  • 🔍 Limited customization options
  • 💰 Desire for free version to remain free

Bugs and requests

Units

Reported bugs

4 issues
  • Crashes when clearing input fields
  • Numerical keypad covers conversion results
  • Incompatibility issues with newer iOS versions
  • Ruler measurements not accurate on all devices

Requested features

5 requests
  • Add nautical units (miles, knots)
  • Improve currency conversion accuracy and updates
  • Allow customization of visible unit categories
  • Add more clothing/shoe size conversions
  • Improve user interface and search functionality

Unit Converter

Reported bugs

2 issues
  • Crashes or freezes on some devices
  • Conversion results not displaying properly

Requested features

3 requests
  • Ability to customize order of conversion units
  • Addition of more specialized units (e.g. astronomical distances)
  • Improved scrolling functionality on all devices

In-app purchases

3 purchases

Units

One-time3
  • Small Tip$0.99
  • Medium Tip$2.99
  • Large Tip$4.99
3 purchases

Unit Converter

Subscriptions2
  • Mila's Tools PRO Monthly$0.991 Month
  • Mila's Tools PRO Yearly$4.991 Year
One-time1
  • Mila's Tools PRO Lifetime$9.99

Questions

Is Units free?
Units is free to download, with in-app purchases available.
Is Unit Converter free?
Unit Converter is free to download, with in-app purchases available.
Which has better reviews, Units or Unit Converter?
Unit Converter is rated higher. Units averages 4.1 out of 5 from 51 ratings, while Unit Converter averages 4.8 from 1.5K ratings.
Do Units or Unit Converter have ads?
Both Units and Unit Converter show ads.
Which is updated more often, Units or Unit Converter?
Units ships an update monthly, and Unit Converter weekly. Most recently, Units was updated on November 6, 2026 and Unit Converter on November 6, 2026.

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