Islamic Inheritance Calculator

How Does Islamic Inheritance Distribution Work?

Islamic inheritance law (ilm al-faraid) is one of the most precisely codified areas of Shariah. Unlike common law systems that grant testamentary freedom, Islamic law prescribes mandatory shares for specific relatives based on their relationship to the deceased. These shares are derived directly from the Quran (Surah An-Nisa, 4:11-12 and 4:176) and the Sunnah of the Prophet Muhammad (peace be upon him).

“Learn the Quran and teach it to the people, and learn the faraid and teach them to the people, for I am a mortal and knowledge will be taken away. A time will come when two men will dispute about a faraid and will find no one to tell them about it.”

What Are the Fixed Shares in Islamic Inheritance?

The Quran specifies six fixed fractions, known as furud muqaddarah, that are assigned to certain heirs called ashab al-furud (owners of ordained shares). These fractions are: one-half (1/2), one-quarter (1/4), one-eighth (1/8), two-thirds (2/3), one-third (1/3), and one-sixth (1/6). Each heir's exact share depends on which other heirs survive the deceased.

What Is the Difference Between Fixed Heirs and Residuary Heirs?

Islamic inheritance law divides heirs into two fundamental categories. Ashab al-furud (fixed-share heirs) receive predetermined Quranic fractions as listed above. Asabah (residuary heirs) receive whatever remains of the estate after the fixed-share heirs have taken their portions. Sons are the primary asabah; if a man dies leaving a wife, mother, and son, the wife receives 1/8, the mother receives 1/6, and the son receives the entire remainder (17/24 of the estate).

When sons and daughters coexist, they share the residuary portion at a 2:1 ratio, with each son receiving twice the share of each daughter. This ratio is explicitly stated in Quran 4:11. The father becomes a residuary heir when there are no male descendants. Full brothers and paternal brothers are also residuary heirs when not blocked by closer relatives.

An important distinction exists in the Ja'fari (Shia) school, which does not recognize the concept of asabah. Instead, the Ja'fari school uses a class-based system where daughters inherit the full remainder when no sons exist, rather than the surplus passing to more distant male relatives. This is one of the most significant differences between Sunni and Shia inheritance law.

How Does the Islamic Inheritance Calculator Handle Multiple Heirs?

When multiple heirs survive the deceased, the calculator applies a systematic process. First, it identifies which heirs are eligible and which are blocked (hajb). Blocking rules prevent more distant relatives from inheriting when closer relatives are alive. For example, a son blocks grandsons, granddaughters, and all siblings from inheriting. The father blocks the grandfather and all siblings (in most schools).

After blocking, the calculator assigns fixed shares to all ashab al-furud, then distributes the remainder to residuary heirs. If the total of fixed shares exceeds the estate (sum > 1), the calculator applies awl, which proportionally reduces all shares so they fit within the available estate. If the total is less than 1 and there are no residuary heirs, radd (return) is applied, proportionally increasing fixed shares to absorb the surplus. In most Sunni schools, the spouse is excluded from radd.

Can You Override Islamic Inheritance Rules with a Will?

Islamic law permits a wasiyyah (testamentary bequest) of up to one-third of the net estate, but only to individuals or causes that do not already inherit under Quranic rules. You cannot use a will to give one child more than another, disinherit a Quranic heir, or alter the prescribed shares. The remaining two-thirds (or more) is distributed strictly according to faraid.

This one-third limit was established by the Prophet Muhammad (peace be upon him) when Sa'd ibn Abi Waqqas asked about bequeathing his entire wealth to charity. The Prophet replied: “One-third, and one-third is a lot. It is better for you to leave your heirs wealthy than to leave them poor, begging from others.” (Sahih al-Bukhari 2742). Any bequest exceeding one-third requires the unanimous consent of all Quranic heirs after the testator's death.

What Happens to Debts and Funeral Expenses Before Inheritance?

Islamic law mandates a strict priority order for estate disbursement. Funeral expenses come first; scholars unanimously agree that a dignified burial is the deceased's first right upon their estate. Next, all outstanding debts must be settled, including financial debts to creditors and religious debts such as unpaid zakat, unfulfilled vows, and missed obligatory fasts requiring fidyah (compensation). The Quran explicitly states that inheritance shares are calculated “after any bequest he may have bequeathed or any debt” (Quran 4:11).

After debts and funeral expenses, valid bequests (wasiyyah) are honored up to the one-third limit. Only the balance remaining after these three deductions is the distributable estate that gets divided among heirs. If debts exceed the total estate, the heirs receive nothing, unlike some Western legal systems, Islamic law does not hold heirs liable for the deceased's debts beyond the estate value. The estate simply absorbs as much debt as it can cover.

Inheritance Rules by School of Jurisprudence

While the core Quranic shares are agreed upon by all schools, important procedural differences exist in how certain complex scenarios are resolved.