Comparison

Inductor Design Pro vs Calculation Transformers

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

Head to head
About

Inductor Design Pro

Read full description

Inductor Design Pro is a secure, offline-first power inductor design tool for power electronics engineers and magnetic component design workflows. Core capabilities: AP-method and LI²-method core selection, joint core-and-winding iteration, Pareto non-dominated filtering with DQS five-dimension scoring (loss, core volume, thermal margin, manufacturability, risk), and automatic multi-candidate comparison. Supports custom material / core / bobbin databases merged with the built-in library. Peak flux density B_max is optional — leave blank to auto-determine from material and operating temperature; if set manually, use values appropriate to the material family to avoid excluding viable cores too early. Topologies: Buck, Boost, Forward (output filter inductor only, not the transformer), and Interleaved Buck (multi-phase, one inductor per phase), with CCM / DCM / BCM modes and full co-evaluation of core, material, air gap, temperature rise, and losses. Parameter sweep: frequency sweep and ripple-ratio / DCM sweep charts visualize how inductance and core size vary with key parameters, helping you trade off switching frequency against core size. Workflow: three-step closed loop (Specifications & Constraints → Core & Winding Selection → Summary & Report), with PDF report and JSON design-file export. Built-in core and wire database included. Privacy & data: core design runs locally; design data stays on your device and is never uploaded to the developer’s servers. Subscription and restore purchases require a network connection. Subscription: Inductor Design Pro Annual Subscription, 1-year term, auto-renews at expiry, $29.99/year (Mainland China ¥198/year; other regions as shown in the App Store). New users get a 14-day full-feature free trial — see the Subscription tab (3rd tab in the app). Manage or cancel anytime in Settings → Apple ID → Subscriptions; no refund for the current period. Privacy commitment: no data collection, no account system. Privacy Policy: https://tobebetter2026.github.io/Public-documents/InductorDesignPro/Privacy-policy.html Terms of Use (Apple Standard EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Calculation Transformers

Features
Read full description

Calculation Transformers is a practical electrical engineering tool designed to help calculate important transformer parameters quickly and accurately. It is suitable for students, technicians, and professionals working with transformer design, maintenance, and analysis. The app simplifies complex electrical formulas and provides reliable outputs in an easy-to-understand format. With a clean interface and fast processing, it becomes a handy reference for daily engineering tasks. Key Features: Fast transformer-related calculations Clear and structured inputs Accurate and easy-to-read results Helpful for design and troubleshooting User-friendly interface Calculation Transformers supports efficient planning and understanding of transformer performance, making it a valuable companion for electrical work. in-app purchase included 
 Lifetime to unlock all calculation and remove ads Privacy Policy : https://docs.google.com/document/d/1Dn1gNdDP2AHL7sg-px4rxdLAcoGHlNB8/edit#heading=h.1ionsc3v3xmq Terms and Condition : https://docs.google.com/document/d/1t-LREPKByKaM0UkbIo4o0E1gdAYs21Oe30EfGxenEss/edit?usp=sharing

Screenshots

Inductor Design Pro4 screens
Calculation Transformers4 screens

Verdict

The call

The clearest difference is update cadence: Inductor Design Pro at every 3 weeks against Calculation Transformers's every 5 months. Calculation Transformers's advantage is iOS requirement (13.0 vs 15.0). On price, 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

Both are free to download. Inductor Design Pro sells 1 in-app purchase, starting at $29.99 per year and Calculation Transformers sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Inductor Design Pro ships an update every 3 weeks, Calculation Transformers every 5 months. The most recent releases landed on July 4, 2026 and September 17, 2026 respectively.

Scorecard2 real differences · 4 level
Inductor Design Pro versus Calculation Transformers: the parameters behind the verdict, then further details
ParameterInductor Design ProCalculation Transformers
PriceFreeFree
Update frequencyEvery 3 weeks — betterEvery 5 months
AdsNoNo
In-app purchasesYesYes
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.013.0 — better
Further details — not scored
Size9 MB56 MB
Age rating4+4+
Developer建忠 徐Nanjibhai Gorasiya

In-app purchases

1 purchases

Inductor Design Pro

Subscriptions1
  • Annual Subscription14 Days trial$29.991 Year
1 purchases

Calculation Transformers

One-time1
  • Lifetime premium$9.99

Questions

Is Inductor Design Pro free?
Inductor Design Pro is free to download, with in-app purchases available.
Is Calculation Transformers free?
Calculation Transformers is free to download, with in-app purchases available.
Do Inductor Design Pro or Calculation Transformers have ads?
Neither Inductor Design Pro nor Calculation Transformers shows ads.
Which is updated more often, Inductor Design Pro or Calculation Transformers?
Inductor Design Pro ships an update every 3 weeks, and Calculation Transformers every 5 months. Most recently, Inductor Design Pro was updated on July 4, 2026 and Calculation Transformers on September 17, 2026.

Other comparisons