Comparison

Converter vs Calculy

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

Head to head
About

Converter

This app offers a comprehensive unit and hardness conversion tool with an easy-to-use interface. It includes currency conversion with updated exchange rates, over 300 engineering and scientific units, and a specialized hardness converter. Additional features like timezone conversion, pace calculation, and a standard calculator enhance its utility.

Highlights
  • Currency converter with live exchange rates
  • Over 300 engineering and scientific units
  • Specialized hardness converter
  • Timezone conversion
  • Running pace calculator
  • Integrated standard calculator
  • Conversion history log
Features
Read full description

Trelleborg’s “Unit and Hardness Converter” converts a comprehensive list of units (incl. currencies) in an easy way. In addition, the app has a set of other useful features on board, like timezone conversion, percentage calculations, a running pace calculator and more What our users say: “Have been using it forever, never tried other converter as this one does the job perfectly” - Lazareth_fr “Fabulous resource, but also a functional masterpiece!” -Otto. “This is needed by all engineers. So simple and easy to use” -JLa03.   FEATURES • Easy-to-use interface • Currency converter with in-app exchange rate update functionality • Over 300 engineering and scientific conversion units in 32 categories • Hardness converter with 16 conversion tables based on ASTM E140-07 and ISO-18265 for quick conversion between different scales • Video library: features the extensive Trelleborg Sealing Solutions YouTube library • Toggle between units • Switch between dark and white theme • Conversion history log • Create favorite lists • Standard calculator integrated with unit converter DIMENSIONS • Area • Currency • Current • Data • Density • Distance • Dynamic Viscosity • Energy • Force • Frequency • Kinematic Viscosity • Moment of inertia • Power • Prefixes • Pressure • Speed • Strength • Temperature • Time • Torque • Volume • Weight • Fuel Consumption • Glucose • Vacuum • Numbers • Illumination • Radioactivity • Radiation (absorbed) • Angles • Volume Flow Rate • Calorie • Metric Prefixes • Typography • Electric Charge OTHER MISCELLANEOUS CATEGORIES • Timezone conversion • Clothing sizes / Shoe sizes • International power plugs • Running pace calculator • Percentage calculator • Pace • Hex, Binary, Decimal • BMI (metric/inch) HARDNESS SCALES INCLUDED • Rockwell (HRC, HRA, HRD, HRF, HRG, HRE, HR-15-N, HR-30N, HR-45-N, HR45-T, HR-15T, HR-30T, HR45-T) • Brinell (HBW, HBS) • Vickers (HV, • Knoop (HK) The app is available in English, German and Chinese languages. Download now or contact us with any questions.

About

Calculy

This free calculator app offers advanced functions beyond basic arithmetic, including a comprehensive unit converter with daily updated currency rates. It supports a wide range of mathematical operations and is available for iPhone and iPad.

Highlights
  • Advanced mathematical functions
  • Unit converter with 220+ units
  • Daily updated currency rates
  • Supports iPad expanded layout
  • Hardware keyboard support on iPad
  • Ad-free experience
Features
Read full description

Calculy is a free calculator for iPhone and iPad. Small yet mighty and totally ad-free. Go beyond basic calculations with Calculy’s full range of functions: • unit converter with more than 220 units from 16 sections (including currencies with daily updated rates) • percentages • square, cube and nth power • square root, cube root and nth root • logarithm, natural logarithm, common logarithm • factorial, reciprocal • rounding • exponentiation to the power of 2, 10, e • Pi, e Euler's number, random numbers • sine, cosine, tangent • arcsine, arccosine, arctangent • hyperbolic sine, hyperbolic cosine, hyperbolic tangent The expanded layout for iPad handily displays all available function keys. Hardware keyboard is supported on the iPad.

Screenshots

Converter4 screens
Calculy4 screens

Verdict

The call

The clearest difference is in-app purchases: Converter at none against Calculy's 3. Converter also leads on ratings volume (981 vs 1). Calculy's advantage is update cadence (every 2 weeks vs every 2 months). On price, rating, review sentiment and ads 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. Calculy sells 3 one-off in-app purchases. Converter asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.9 for Converter against 5.0 for Calculy. That said, the two scores are not equally well evidenced: Converter has 981 ratings behind it against 1, so its average is the more settled of the two. Written reviews are what separate them: 94% of Converter's written reviews are positive against 91% of Calculy's.

UpkeepUpdate frequency

Converter ships an update every 2 months, Calculy every 2 weeks. The most recent releases landed on November 6, 2026 and November 3, 2026 respectively.

Scorecard3 real differences · 7 level
Converter versus Calculy: the parameters behind the verdict, then further details
ParameterConverterCalculy
PriceFreeFree
Rating4.9 (981 ratings)5.0 (1 ratings) — better
Positive reviews93.9% of reviews — better91.3% of reviews
Number of ratings981 — better1
Update frequencyEvery 2 monthsEvery 2 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFreeFree
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.615.0 — better
Further details — not scored
Size37 MB3 MB
Age rating12+4+
DeveloperTrelleborg Sealing SolutionsLingo4you Mario Muller und Heike Pahlow GbR

Customer experience

Converter

All ratings897 ratings
Positive98.1%
Neutral1.3%
Negative0.6%
Written reviews608 reviews
Positive93.9%
Neutral3.3%
Negative2.8%

Calculy

Written reviews23 reviews
Positive91.3%
Neutral0.0%
Negative8.7%

Bugs and requests

Converter

Reported bugs

2 issues
  • Occasional crashes on startup for non-English/German users
  • Conversion from meters to feet does not show inches

Requested features

3 requests
  • Add fuel efficiency conversions
  • Allow users to set favorite conversions as default
  • Improve currency conversion rate updates

Calculy

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Converter

No in-app purchases

3 purchases

Calculy

One-time3
  • Buy me a coffee$0.99
  • Buy me cookies$1.99
  • Buy me a pizza$3.99

Questions

Is Converter free?
Converter is free to download, with no in-app purchases.
Is Calculy free?
Calculy is free to download, with in-app purchases available.
Which has better reviews, Converter or Calculy?
Calculy is rated higher. Converter averages 4.9 out of 5 from 981 ratings, while Calculy averages 5.0 from 1 ratings.
Do Converter or Calculy have ads?
Neither Converter nor Calculy shows ads.
Which is updated more often, Converter or Calculy?
Converter ships an update every 2 months, and Calculy every 2 weeks. Most recently, Converter was updated on November 6, 2026 and Calculy on November 3, 2026.

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