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App Name: Magnet Weight Calculator (MagCal)
Developer: Klas Lu
Last Updated: June 8, 2026

中文版  ·  Privacy Policy

About the App

Magnet Weight Calculator is a practical tool for magnet industry professionals. It quickly estimates magnet weight based on material type, shape, and dimensions. All calculations are performed locally on your device — no internet connection required.

How to Use

  1. Select a magnet material, or tap "Parameters" to customize material density.
  2. Choose a shape: Block, Cylinder, Ring, or Custom.
  3. Enter the corresponding dimensions in millimeters.
  4. Tap "Calculate Weight" to view the weight and volume results.

When entering dimensions, the numeric keyboard appears and the "Calculate Weight" button automatically moves above it, so you can tap it at any time.

Supported Shapes & Formulas

All dimensions are in millimeters (mm), volume in cubic millimeters (mm³), and density in grams per cubic centimeter (g/cm³).

Block

Enter length, width, and height.

Volume = Length × Width × Height

Cylinder

Enter diameter and height.

Volume = π × (Diameter ÷ 2)² × Height

Ring

Enter outer diameter, inner diameter, and height. Outer diameter must be greater than inner diameter.

Volume = π × [(OD ÷ 2)² − (ID ÷ 2)²] × Height

Custom

Enter the product volume (mm³) directly for complex shapes that cannot be calculated with standard formulas.

Weight Calculation

Weight (g) = Volume (mm³) × Density (g/cm³) ÷ 1000

Results are displayed to 4 decimal places.

Parameter Settings

Tap "Parameters" on the main screen to manage the magnet material list:

Built-in default materials include: Sintered NdFeB, Bonded NdFeB, SmCo, Ferrite, Alnico, and FeCrCo. You can adjust density values to match your specific grades.

All settings are stored locally on your device and will be deleted when you uninstall the App.

Frequently Asked Questions

Why can't I get a result?

Make sure all dimensions are valid numbers greater than 0. For ring shapes, the outer diameter must be greater than the inner diameter. Also check that you haven't entered spaces or non-numeric characters.

How accurate are the results?

The App calculates theoretical weight based on geometric volume and density. Results are estimates only. Actual product weight may vary due to material grade, sintering/bonding process, tolerances, coatings, and other factors. Always verify with physical measurements.

What languages are supported?

The App interface follows your system language: Chinese when the system language is Chinese, English otherwise.

Does the App require internet?

No. The App works entirely offline and does not collect or upload your data. See our Privacy Policy for details.

How do I reset all material parameters?

Go to "Parameters" and tap "Reset Defaults" to restore all material types and densities to system presets.

System Requirements

Contact Us

If you encounter issues, find a bug, or have feature suggestions, please contact the developer:

Developer: Klas Lu
Email: klas.lu@qq.com

When sending an email, please include your device model, iOS version, a description of the issue, and the steps to reproduce it. This helps us resolve your problem faster.

You may also reach us through the App's product page on the App Store.