There's No Single Answer, Only a Formula
"How much does a daughter inherit?" doesn't have one fixed answer, because a daughter's share depends entirely on who else survives alongside her: whether there's a son, how many daughters there are, whether the father or grandfather is alive, and which school of jurisprudence applies. What follows are the governing rules for each relationship, not a single number, because the single number genuinely doesn't exist independent of the full family picture.
A Daughter's Share: The Baseline Rules
Under Surah An-Nisa 4:11, a single surviving daughter (with no sons) takes a fixed 1/2 of the estate. Two or more daughters, with no sons, collectively take a fixed 2/3, split equally among them. Where a son is also present, the fixed-share rule no longer applies at all, daughters instead become residuary ('asabah) heirs alongside their brothers, inheriting in a 2:1 ratio (each son receives double each daughter's share) from whatever remains after other fixed-share heirs (a surviving spouse, parents) take their portions.
A Wife's Share: The Baseline Rules
Under Surah An-Nisa 4:12, a surviving wife takes 1/4 of the estate if the deceased husband left no children, or 1/8 if he did. If there are multiple wives, that same fraction (1/4 or 1/8) is the total pool split equally among all of them, not 1/4 or 1/8 each. A wife's share is always a fixed portion; she never becomes a residuary heir under any of the six schools.
A Son's Share: The Baseline Rules
A son is never a fixed-share heir, he's always residuary. If he's the only child, he takes the entire estate remaining after other fixed-share heirs (spouse, parents) are paid. If there are daughters as well, he inherits alongside them at double each daughter's share (asaba bi ghayrihi for the daughters, asaba bi nafsihi for himself). If there are multiple sons and no daughters, they split the residuary estate equally among themselves.
Where Hanafi, Shafi'i, Maliki, and Hanbali Actually Agree
On these three baseline relationships, the four Sunni schools are in close agreement, the Quranic fractions above (1/2, 2/3, 1/4, 1/8) and the 2:1 son-to-daughter residuary ratio are shared across all four. Real Sunni divergence tends to show up elsewhere: in exactly which more distant relatives count as blocking or blocked (hajb), in the details of 'awl and radd, and in specific edge cases involving grandparents or siblings, not in these three core relationships.
Where the Ja'fari School Diverges Meaningfully
The Ja'fari (Twelver Shia) school produces genuinely different outcomes in specific configurations because of its class (tabaqat) system, most notably: a single daughter with no sons and no other Class I relatives can inherit the entire estate under Ja'fari fiqh (as fixed-share plus radd), where the Sunni schools would cap her at a fixed 1/2 and pass the remainder to other relatives like siblings or a grandfather. This is one of the clearest, most concrete divergence points across the six schools, and exactly the kind of thing worth verifying against your own family's actual configuration rather than assuming.
Ahle Hadees and the Sunni Baseline
Ahle Hadees (Salafi) methodology generally follows the same Quranic fraction framework as the four Sunni schools for these core relationships, since the fixed shares themselves come directly from the Quranic text rather than from later juristic reasoning where the schools more commonly diverge. Differences, where they exist, tend to appear in secondary rulings rather than in the baseline daughter, wife, and son fractions.
Why Your Actual Family Structure Is the Real Variable
Every fraction above is conditional, not absolute. A single sentence like "a daughter gets half" is true in exactly one family configuration and wrong in most others. The only reliable way to know what a specific daughter, wife, or son actually inherits is to run the complete family structure, doctrine, and estate through a proper calculation, which is precisely why Wasiyat's engine outputs a full citation trail for every share rather than a single number without its conditions attached.