Allah subhana watahala says in the only Quran (surah al-Nisa 4 verse 11).
“Allah instructs you concerning your children’s (inheritance): a male receives a share equal to that of two females. But if they (the children) are only women, and are more than (or equal to) two, their share is two thirds of that which he (the deceased) had left. And if there is only one female, her share is half (of the estate). And his parents, each one’s share is a sixth of that which he left if he had children. But if he had no children, and the parents inherit from him, the mother’s share is one third. And if he had siblings, the mother’s share is a sixth. (These distributions should be done) after the payment of any bequeathals that he may have made or debts. (that he may have had). Your parents and offspring – you do not know which among them are nearest to you in benefit. (These shares are) an ordainment imposed by Allah. Indeed, Allah is knowing and wise”
Allah (subuhanahu wa ta’ala) says in the Holy Quran (Surah al- Nisa(4) verse 12):
“You receive one half of that which your wives leave if they have no child. If they have a child, you receive one fourth of what they leave – after payment of any bequeathal that they had made or debts (that they had). And they receive one fourth of that which you leave if you have no child. If you have a child, they receive one eighth of what you leave – after payment of any bequeathal that you had made or debts (that you had). If the man or woman whose inheritance is in question has neither ascendants nor descendents, but has a (maternal) brother or sister, each one of them is to receive a sixth; and if they were more than two, they share a third – after payment of any bequeathals that had been made or debts (that are owed), and that are not intended to cause harm (to the legal inheritance). This is a commandment from Allah; and Allah is over knowing and tolerant.”
Allah (subhanahu wa ta’ala) says in the Holy Quran (surah al – Nisa(4) verse 176).
“They ask thee for a legal decision. Say: Allah directs (they) about those who leave no descendants as heirs. If it’s a man that dies leaving a sister but no child she shall have half the inheritance: if (such a deceased was) a woman who left no child her brother takes her inheritance: if there are two sisters they shall have two third of the inheritance (between them); if there are brothers and sisters (they share), the male having twice the share of the female. Thus doth Allah make clear to you (His law) lest ye err. And Allah hath knowledge of all things.”