A free Islamic inheritance (mīrāth) calculator that runs entirely in the browser. You mark which relatives of the deceased are alive, enter the estate, and it shows each heir's share as a fraction, a percentage and an amount, with the rule behind every share. Arabic by default, with a full English version.
⚠️ For educational reference only. Not a fatwa. Please confirm your case with a qualified scholar.
The app opens on a ready-made example: Salem Rashid Al Dhaheri leaves an estate of 1,000,000 AED with a 100,000 AED bequest. His wife, son, two daughters, mother and paternal grandfather are alive; his father has died; his uncle is blocked by the son.
| Heir | Rule | Share of the net estate | Amount (AED) |
|---|---|---|---|
| Wife | 2b | 1/8 | 112,500.00 |
| Son | 14, 15 | 13/48 | 243,750.00 |
| Each daughter (×2) | 14, 15 | 13/96 | 121,875.00 |
| Mother | 6b | 1/6 | 150,000.00 |
| Grandfather | 7a | 1/6 | 150,000.00 |
| Uncle | 13a | Blocked by the son | 0 |
| Total | 1 | 900,000.00 |
- Exact fractions: shares are computed with BigInt rational arithmetic, never floating point. Amounts are split by the largest-remainder method, so they always add up to the estate to the cent.
- All 29 standard heirs: spouses, descendants, parents and grandparents, the three kinds of siblings, nephews, uncles and cousins.
- Every classical case:
- blocking (ḥajb)
- the 2:1 ratio for residuary heirs
- ʿAwl and Radd
- Umar's case (العُمَريّتان)
- the Mushtaraka case
- grandfather with siblings
- Akdariyya
- Bequest (wasiyya): paid before the heirs and capped at one third of the estate, with a warning if it exceeds the limit.
- Checked against 133 reference cases: taken from scholars' textbooks (see Accuracy).
- Relatives are laid out as a family tree. Click a circle to mark someone alive: it turns green and shows its share.
- Add wives (up to 4), sons, daughters and siblings with +, and give everyone a real name.
- Smart display: only relatives who could change the result are shown. The others are listed with the reason (e.g. "blocked by the son").
- Blocked heirs show a red محجوب badge with the rule that blocks them.
- Summary tiles, a bar chart and a full table: fraction, percentage of the estate and amount for each person.
- Rules applied: every step cites its rule; click a rule to read its full text (44 rules, in Arabic and English).
- Banners explain special cases such as ʿAwl, Radd and Umar's case when they occur.
- Right-to-left Arabic interface, with correct singular/dual/plural forms, gender agreement (محجوب / محجوبة) and grammatical case.
- One click switches to English. Example names are translated; names you type are kept as written.
- PDF report: includes the family tree, the results and the rules. It is rendered at laptop width on every device, so phones produce the same compact A4 report as computers.
- Share links: reopen the exact same calculation. They carry relations and amounts only, never names.
- One-tap sharing to WhatsApp, X, LinkedIn, Facebook, Telegram and email, or the phone's own share sheet.
- Responsive from 320px phones to large screens; the tree scales itself to fit.
- Dark mode, reduced-motion support, large touch targets and keyboard access.
- Everything is calculated in your browser. There is no server and no account, and names and amounts are never uploaded.
- Anonymous, cookie-free statistics (Umami) count visits, PDF downloads, shares per channel and rules opened. They never record names, amounts, heirs or the contents of share links. They respect Do Not Track and only run on the live site.
- To exclude your own visits, run this in your browser console on the live site:
localStorage.setItem('umami.disabled', 1).
calculate(heirs, gender) in app/src/engine/calculate.ts runs these steps in order:
- Blocking (Rule 13). Living heirs exclude the relatives they outrank.
- Prescribed shares (Rules 1–12). Fixed Qurʾanic fractions for spouses, parents, grandparents, daughters, sisters and maternal siblings.
- Special cases. Umar's case (21), grandfather with siblings (23) and Akdariyya (18a, 24).
- ʿAwl (Rule 18) or residue (Rule 14). If shares exceed the estate, they are scaled down proportionally. Otherwise the residuary heirs take what remains, males and females of the same class at 2:1 (Rules 15, 44).
- Radd (Rule 19). Any remainder with no residuary heir returns to the heirs, except the spouse.
- Mushtaraka (Rule 22). Full brothers never receive less than maternal siblings.
Details are in app/README.md and ANALYSIS.md.
- 155 automated tests, including the 133 reference cases in test-cases/. For each case, every category share and every individual share must match exactly.
- Run on every push by GitHub Actions; the site is only redeployed when all tests pass.
- Where the reference data has gaps or errors, the app follows the reference:
- #29 is empty on the reference site and is skipped.
- #127: the reference table shows the wrong share per maternal brother, so only the category totals are compared.
- #34 (daughters with maternal brothers): the app follows the reference rule, under which maternal brothers inherit. Classical fiqh would have the daughters block them.
| App | React 18, TypeScript, Vite |
| Calculation | Pure TypeScript engine with BigInt fractions, no UI imports |
| Tests | Vitest |
| html-to-image + jsPDF, loaded only when exporting | |
| Font | IBM Plex Sans Arabic, bundled locally via Fontsource |
| Statistics | Umami Cloud (cookie-free) |
| Hosting | GitHub Pages, deployed by GitHub Actions |
Requires Node.js 18 or later.
git clone https://github.com/thabet-noob/inheritance-in-islam.git
cd inheritance-in-islam/app
npm install
npm run dev # http://localhost:5173
npm test # run the 155 tests
npm run build # type-check and build the static site into app/dist/Useful URL options: ?lang=en opens the app in English; a #s=… share link opens a shared calculation.
Every push to main runs .github/workflows/ci.yml:
- Install dependencies, run the tests and build.
- If everything passes, publish
app/dist/to GitHub Pages.
Pull requests are tested but never published. A release is live about a minute after pushing.
├── app/ The web app — see app/README.md
│ ├── src/engine/ Calculation engine: fractions, heirs, rules, money, relevance
│ ├── src/i18n/ Arabic & English text and step messages
│ ├── src/ui/ Family tree, results, rules, sharing, PDF export
│ ├── src/data/ The 44 rules in English and Arabic
│ └── tests/ Engine, translation and share-link tests
├── test-cases/ 134 reference cases (JSON + readable text)
├── rules/rules.txt The 44 inheritance rules
├── ANALYSIS.md How the rules and reference cases fit together
├── img/standard-heirs.png Diagram of the 29 standard heirs
└── .github/workflows/ CI and GitHub Pages deployment
The rules, the reference test cases, the FAQ (questions.txt), the input form (home-page.html) and the heirs diagram come from the Islamic Inheritance Calculator at ilmsummit.org. They are included with credit so the calculation can be checked against them, and they remain the property of their owners. That site's own references are:
- Inheritance — Regulations & Exhortations, Muhammad Al-Jibaly
- The Islamic Law of Succession, Dr. A. Hussain
The code is released under the MIT License; it does not cover the reference material credited above.
© 2026 Thabet Chelligue