Islamic Inheritance Calculator

NB: This is a work in progress. If you spot an error in the calculations, please file an issue.

This package calculates Islamic inheritance shares based on the Sunni schools of jurisprudence. Currently supports madhhab-specific logic (e.g. Hanafi, Shafi'i).

📦 Installation

npm install webevis-inheritance-calculator

🚀 Usage

import { calculate } from 'webevis-inheritance-calculator'
import Fraction from 'fraction.js'

function printResults(results) {
  const fractionToString = (r) => ({ ...r, share: r.share.toFraction(true) })
  console.log(results.map(fractionToString))
}

const result = calculate({ wife: 3, son: 1, daughter: 1 }, 'hanafi')

printResults(result)
// [
//   { name: 'wife',     count: 3, type: 'fard',  share: '1/8'  },
//   { name: 'son',      count: 1, type: 'tasib', share: '7/12' },
//   { name: 'daughter', count: 1, type: 'tasib', share: '7/24' }
// ]

🧮 Parameters

• heirs: Record<string, number> – A key-value object of heir names and their counts.
• madhhab: 'hanafi' | 'shafii' | 'maliki' | 'hanbali' (optional, default: 'hanafi')

⚖ Supported Features

• ✅ Fard (obligatory) shares
• ✅ Taʿṣīb (residuary) shares
• ✅ Blocking (ḥajb) logic
• ✅ Awl (reduction when shares exceed estate)
• ✅ Radd (redistribution when shares are less than 1)
• ✅ Multiple wives (shared 1/8)
• ✅ Madhhab-specific differences (e.g. grandfather with siblings)

🧪 Testing

Run all test cases using:

npm test

📬 Contributing

Pull requests are welcome! For major changes, please open an issue first to discuss what you would like to change.

📜 License

MIT License © Webevis