The obligatory alms, the categories of wealth it touches, and the difference from khums.
Is zakat obligatory in the Shia school outside the well-known categories?
Zakat on the named categories of wealth is agreed; the extension to other forms of property is disputed, with several authorities recommending precaution.
What is the minimum threshold and rate?
Thresholds (nisab) and rates are specified per category and per authority.
Who is entitled to receive zakat?
The Quran lists eight categories; the scope of some, and the requirement of faith or descent in others, is derived.
Is zakat separate from khums?
They are distinct levies on different bases, and the distinction is a frequent source of practical confusion.
Is zakat al-fitr part of this?
The end-of-Ramadan payment is a separate obligation with its own measure and timing.
خُذْ مِنْ أَمْوَٰلِهِمْ صَدَقَةًۭ تُطَهِّرُهُمْ وَتُزَكِّيهِم بِهَا وَصَلِّ عَلَيْهِمْ ۖ إِنَّ صَلَوٰتَكَ سَكَنٌۭ لَّهُمْ ۗ وَٱللَّهُ سَمِيعٌ عَلِيمٌ
Take, [O, Muhammad], from their wealth a charity by which you purify them and cause them increase, and invoke [Allah 's blessings] upon them. Indeed, your invocations are reassurance for them. And Allah is Hearing and Knowing.
وَأَقِيمُوا۟ ٱلصَّلَوٰةَ وَءَاتُوا۟ ٱلزَّكَوٰةَ ۚ وَمَا تُقَدِّمُوا۟ لِأَنفُسِكُم مِّنْ خَيْرٍۢ تَجِدُوهُ عِندَ ٱللَّهِ ۗ إِنَّ ٱللَّهَ بِمَا تَعْمَلُونَ بَصِيرٌۭ
And establish prayer and give zakah, and whatever good you put forward for yourselves - you will find it with Allah. Indeed, Allah of what you do, is Seeing.