What this calculator covers, and what it does not
The Quran gives both men and women a share of what parents and close relatives leave, “be it little or much” (4:7). This calculator divides an estate among the heirs closest to the deceased: a husband or up to four wives, sons, daughters, the father and the mother. It asks how many siblings there are only because two or more reduce the mother’s share; it does not give the siblings a share.
It does not cover grandparents, grandchildren, brothers and sisters as heirs, uncles, cousins or any other relative, nor special cases such as an unborn child, a missing person, or relatives who died in the same accident. When those heirs are involved, the rules of exclusion (hajb) interact in ways that need someone who knows the whole science, and the calculator says so rather than guessing.
What comes out of the estate first
Before anyone inherits, the estate pays for a funeral and burial of reasonable cost, then the deceased’s debts, including any unpaid mahr owed to a wife, and then any bequest. The Quran says four times, in 4:11 and 4:12, that the shares are paid after any bequest or debt. The majority of scholars pay debts before the bequest, because a debt is owed to someone else while a bequest is a gift. Only what remains is divided among the heirs, and that remainder is the figure to enter above.
The one-third limit on bequests
A Muslim may leave up to one third of the estate by will to people or causes of their choosing. Anything above a third takes effect only if the heirs agree after the death. A bequest to someone who already inherits, such as extra money to one child, takes effect in the view of the four schools only if the other heirs consent.
So a will cannot be used to change the Quranic shares. It can be used to provide for someone who does not inherit: a grandchild whose parent died first, a stepchild, a relative in need, or a charity. Several Muslim-majority countries have written an obligatory bequest for orphaned grandchildren into their law.
The fixed shares
4:11 sets the shares of children and parents, 4:12 those of spouses and of maternal half-siblings, and 4:176 those of brothers and sisters when the deceased leaves no child. For the heirs this calculator covers, the fixed shares are:
Husband: a half if his wife left no child, a quarter if she did (4:12). Wife: a quarter if her husband left no child, an eighth if he did; several wives share that fraction equally (4:12). One daughter with no son: a half. Two or more daughters with no son: two thirds, shared (4:11). The verse speaks of daughters “more than two”; the four schools give two daughters the same two thirds, reading it alongside 4:176, which gives two sisters two thirds. Mother: a sixth if there is a child or two or more siblings, otherwise a third (4:11). Father: a sixth if there is a child (4:11), and more as a residuary, as below.
One case is settled differently from the most literal reading. When the only heirs are a spouse and both parents, the four schools give the mother a third of what is left after the spouse’s share, not a third of the whole estate, so that the father does not receive less than the mother.
The residuaries (ʿaṣaba)
Whatever the fixed shares leave goes to the residuary: the nearest male relative through the male line. A son is the strongest. When there is a son, the children share what remains, each son taking twice what each daughter takes, and the daughters no longer have a fixed share. With no son, the father is the residuary, and if there are only daughters he takes his sixth and then the rest. With neither son nor father, the residue passes to brothers, then their sons, then uncles and their sons: the wider circle this calculator does not distribute.
When the shares add up to more than the whole: ʿawl
Sometimes the fixed fractions come to more than one estate. Then every share is reduced in proportion, which is called ʿawl. It has been the practice since the time of the caliph ʿUmar, and the four schools follow it.
Example: a woman dies leaving her husband, two daughters and her mother. The husband’s quarter is 3/12, the daughters’ two thirds 8/12 and the mother’s sixth 2/12, which makes 13/12. Instead of twelve parts the estate is divided into thirteen: 3/13 to the husband, 8/13 to the two daughters together, and 2/13 to the mother. On an estate of 130,000 that is 30,000, 80,000 and 20,000.
When they add up to less and no one takes the rest: radd
If the fixed shares leave something over and there is no residuary, the surplus returns to the fixed-share heirs in proportion to their shares. This is radd. In the majority view a spouse does not share in it. It is the Hanafi and Hanbali position; the earlier Maliki and Shafiʿi position sent the surplus to the public treasury, and later scholars of both schools adopted radd where no properly run treasury exists.
Example: a man dies leaving his mother and one daughter. The mother’s sixth and the daughter’s half make 4/6, leaving 2/6 with no residuary. The whole is shared between them in the ratio 1 to 3: a quarter to the mother and three quarters to the daughter. If his wife also survives him, she takes her eighth first, and the remaining seven eighths are divided between the mother and daughter in the same 1 to 3 ratio: 7/32 and 21/32.
Why a son receives twice a daughter’s share
The rule is in the text of 4:11: “for the male, what is equal to the share of two females.” The explanation usually given is the division of financial duties in Islamic law. A husband must pay his wife’s mahr and maintain her and their children, and a son may become responsible for his parents and unmarried sisters. A woman’s own property, including her mahr and her inheritance, belongs to her alone, and she is not obliged to spend it on the household. 4:34 ties the man’s role in the family to what he spends from his wealth.
Nor is two-to-one a general rule for every man and woman. The mother and father each take a sixth when there are children (4:11), and maternal half-brothers and half-sisters share their portion equally (4:12).
Who does not inherit
The four schools agree that a person who unlawfully kills the deceased does not inherit from them, and that a Muslim and a non-Muslim do not inherit from each other. A non-Muslim relative can still be provided for through a bequest within the one-third limit.
Civil law may divide your estate differently
Where you live, an estate may be divided by civil law rather than by these shares. Many countries divide equally between sons and daughters and give a surviving spouse a much larger share than the Quranic one, and in many the civil rules apply automatically unless there is a valid will. If you want your estate divided by Islamic rules, you will usually need a will that is valid under your country’s law, drawn up with a lawyer who understands both. The result on this page is educational: it is not a legal ruling, and it is not legal or financial advice.