Comparison

Unit Converter For Engineers vs Hardness Conversion Master

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

Head to head
About

Unit Converter For Engineers

This app provides a comprehensive unit conversion tool specifically designed for engineers, offering specialized units not found in standard converters. It features offline functionality, fast search, and a clean interface, replacing the need for multiple reference materials.

Highlights
  • Specialized engineering units
  • Offline functionality
  • Fast search and instant conversion
  • Fraction input mode
  • Ad-free interface
  • Scientific notation support
Features
Read full description

Built for engineers who work with units most converters don’t have. No ads. No popups. No distractions. If you’ve ever opened PDFs, charts, or old handbooks to convert Rockwell hardness, wire gauge, HVAC airflow, radiation dose, water hardness, or torque units — this app replaces all of that. Units you usually can’t find in converter apps Material Hardness Rockwell (HRC, HRB, HRA), Vickers, Brinell, Knoop, Mohs, Shore Wire Gauge AWG, SWG, MCM, kcmil, diameter, cross-sectional area HVAC & Airflow CFM, ACH, BTU/h, tons of cooling, kW, airflow per area and per person Water Quality & Chemistry ppm, mg/L as CaCO₃, grains per gallon (US/UK), °dH, °fH, dKH, mmol/L, meq/L Radiation & Radioactivity Becquerel, Curie, Gray, rad Mechanical & Structural Torque, stress, density, pressure, moment of inertia (kg·m² ↔ slug·ft²) Built for real work environments • Works 100% offline in labs, plants, and job sites • Fast search and instant conversion • Scientific notation for precision work • Fraction input mode for field and construction use • Clean, engineer-friendly interface — no ads, ever This app replaces reference charts, calculators, handbooks, and repeated Google searches with one reliable tool in your pocket. Pricing 7-Day Free Trial $9.99/year full access $29.99 lifetime access Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://unitconvertx.github.io/docs/privacy.html

About

Hardness Conversion Master

Features
Read full description

A professional hardness conversion tool designed for mechanical engineering, metal heat treatment, and quality management, providing quick, stable, and traceable engineering reference data. **Key Features** 1. **Industrial-Grade Precision** The conversion logic is based on ASTM E140 / ASTM A370 standards, utilizing high-density reference points and linear interpolation to deliver stable and reproducible conversion results. 2. **Flexible Input and Real-Time Synchronization** Allows direct input in any hardness field (e.g., HRC / HV / HBW), with real-time conversion across other units, enhancing on-site operational efficiency. 3. **Physical Range Protection Mechanism** Built-in effective range checks for each scale, displaying "No Reference Value" when out of range, reducing the risk of misinterpretation. 4. **Customizable Interface** Enables toggling unit displays and drag-and-drop sorting to create a workspace tailored to individual or production line processes. 5. **Image Conversion (Beta)** Supports photo/album import, area selection recognition, result comparison, and manual correction, suitable for quick conversion of reports and on-site records. 6. **Batch Conversion** Allows multiple data entries for rapid conversion, retaining the last used unit preference to minimize repetitive actions. **Supported Units** - Rockwell: HRC, HRA, HRB, HRD, HRF - Superficial Rockwell: HR15N, HR30N, HR45N, HR15T, HR30T, HR45T - Brinell: HB, HBW - Vickers: HV - Tensile Strength: MPa

Screenshots

Unit Converter For Engineers4 screens
Hardness Conversion Master4 screens

Verdict

The call

The clearest difference is ads: Unit Converter For Engineers at none against Hardness Conversion Master's shown. Hardness Conversion Master's advantage is update cadence (every 3 days vs every 9 days). On price, in-app purchases, device support and iOS requirement 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. Unit Converter For Engineers sells 2 in-app purchases, starting at $9.99 per year and Hardness Conversion Master sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Unit Converter For Engineers ships an update every 9 days, Hardness Conversion Master every 3 days. The most recent releases landed on September 18, 2026 and August 31, 2026 respectively.

Scorecard2 real differences · 8 level
Unit Converter For Engineers versus Hardness Conversion Master: the parameters behind the verdict, then further details
ParameterUnit Converter For EngineersHardness Conversion Master
PriceFreeFree
Rating5.0 (3 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings3 — better—
Update frequencyEvery 9 daysEvery 3 days — better
AdsNo — betterYes
In-app purchasesYesYes
MonetizationFreemium—
DevicesiPhone, iPadiPhone, iPad
Requires iOS16.2 — better17.6
Further details — not scored
Size5 MB259 MB
Age rating17+4+
DeveloperAmanuel AbebawPOYU WANG

In-app purchases

2 purchases

Unit Converter For Engineers

Subscriptions1
  • Annual Subscription7 Days trial$9.991 Year
One-time1
  • Lifetime Access$29.99
1 purchases

Hardness Conversion Master

One-time1
  • Unlock Pro$1.99

Questions

Is Unit Converter For Engineers free?
Unit Converter For Engineers is free to download, with in-app purchases available.
Is Hardness Conversion Master free?
Hardness Conversion Master is free to download, with in-app purchases available.
Do Unit Converter For Engineers or Hardness Conversion Master have ads?
Hardness Conversion Master shows ads; Unit Converter For Engineers does not.
Which is updated more often, Unit Converter For Engineers or Hardness Conversion Master?
Unit Converter For Engineers ships an update every 9 days, and Hardness Conversion Master every 3 days. Most recently, Unit Converter For Engineers was updated on September 18, 2026 and Hardness Conversion Master on August 31, 2026.

Other comparisons