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Khums Calculator (Shia) | Compute 20% Khums After Expenses

The Khums calculator (Shia) works out the 20% Khums due on your annual surplus after legitimate living expenses, split between the share of the Imam and the share of the sadat.

Last updated: June 2026 · Free · No sign-up required

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Results

Enter values above and click Calculate to see your result instantly.

Quick reference

Income − expensesKhums (20%)Each sahm
$4,000$800$400
$8,000$1,600$800
$20,000$4,000$2,000

volunteer_activism Year-end surplus

pie_chart Two shares

verified Clear method

Interpretation guide

ShareGoes to
Sahm al-Imam (half)Via your marja’s office — religious/community works
Sahm al-Sadat (half)Needy sayyids (descendants of the Prophet ﷺ)

lightbulb Worked example

Let's say you are using the Khums Calculator (Shia). The Khums calculator (Shia) works out the 20% Khums due on your annual surplus after legitimate living expenses, split between the share of the Imam and the share of the sadat. Enter the values that match your situation into the input fields and press calculate — using realistic numbers makes the result directly useful for you.

Result: The calculator instantly applies the formula Khums = 20% × max(0, annual income − annual living expenses); split 50/50 Imam/Sadat and returns the result with appropriate precision.

What this means: Read the result in the context of what you are measuring. The step-by-step breakdown lets you confirm the math and understand which input most affects the outcome.

Formula & methodology

Formula: Khums = 20% × max(0, annual income − annual living expenses); split 50/50 Imam/Sadat

The Khums Calculator (Shia) is built on a well-established calculation method. It uses the formula Khums = 20% × max(0, annual income − annual living expenses); split 50/50 Imam/Sadat to turn your inputs into a reliable result. The Khums calculator (Shia) works out the 20% Khums due on your annual surplus after legitimate living expenses, split between the share of the Imam and the share of the sadat. The steps are shown on the page so you can follow the reasoning from input to output.

  1. Set your khums year-end date, then enter the year’s income/gains and genuine living expenses.
  2. The surplus is taxed at one-fifth.
  3. The result splits evenly into Sahm al-Imam and Sahm al-Sadat.

Worked example: $40,000 income − $32,000 expenses = $8,000 surplus → $1,600 khums, paid as $800 Sahm al-Imam + $800 Sahm al-Sadat.

Authoritative source: timeanddate.com

Frequently asked questions

What is Khums?
In Twelver Shia fiqh, khums is an annual 20% levy on surplus income — what remains after a year's legitimate living expenses — plus certain other categories like minerals, treasure, and lawful wealth mixed with unlawful. Half goes to the Imam's share (given to a marja' in the occultation) and half to the poor descendants of the Prophet. This tool calculates the surplus portion.
What expenses are deductible?
The commonly accepted deduction is the amount spent on the dependents' yearly living expenses — food, clothing, housing, education, and medical needs — because khums is paid on surplus at year's end, not on what was consumed. Debts owed and business capital in use are also excluded by many maraji'. Enter your annual income and these living costs and the tool returns the surplus subject to khums.
When do I pay Khums?
Khums is due at your khums year-end — the anniversary of when you first became mukallaf or when you chose a khums date — on any surplus wealth that has not been spent or invested during the year. You may pay it at any time during the year, but many Shia Muslims settle it before the month of Muharram or Ramadan. The calculator works from your annual surplus.
Where does the money go?
Khums is divided into two halves: the share of the Imam (Sahm al-Imam), which in the era of occultation is given to a qualified marja' for religious and charitable purposes, and the share of the poor among the descendants of the Prophet (Sahm al-Sadat). Your marja' provides guidance on disbursement. The calculator shows the split so you can plan.
Do Sunnis pay Khums on income?
The Khums Calculator (Shia) is free, private, and accurate: it runs entirely in your browser (no uploads, no accounts), applies the standard calculation, and explains each step so you can verify the result. The Khums calculator (Shia) works out the 20% Khums due on your annual surplus after legitimate living expenses, split between the share of the Imam and the share of the sadat. There is no limit on usage, and it works on any device.
What does the Khums Calculator (Shia) do?
The Khums calculator (Shia) works out the 20% Khums due on your annual surplus after legitimate living expenses, split between the share of the Imam and the share of the sadat. The calculator takes your inputs, applies the standard calculation, and returns a clear result so you can make an informed decision without doing the math by hand.
What formula does the Khums Calculator (Shia) use?
It computes Khums = 20% × max(0, annual income − exempt expenses − exempt debts), with the result split into the two halves: the Imam's share and the Sadat's share. Enter your income, deductible living expenses, and any exempt debts, and the tool returns the total khums due and the breakdown for each portion.
Is the Khums Calculator (Shia) free and private?
Yes — the Khums Calculator (Shia). There is no sign-up, no paywall, no trial, and no limit on how many calculations you can run. CalcaTools covers its costs with non-intrusive display advertising, so the calculator itself never asks for payment or restricts any feature.
How accurate is the Khums Calculator (Shia)?
The Khums Calculator (Shia) applies the standard formula: Khums = 20% × max(0, annual income − annual living expenses); split 50/50 Imam/Sadat. It is tested against published worked examples before launch and uses native double-precision arithmetic, so results are accurate to typical precision for the values you enter — with no intermediate rounding that could distort the answer.

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