Using the Islamic Inheritance Program (IRTH)

The IRTH program is based on the book "Fiqh-us-Sunna" by Assayyed Sabeq. It was tested against over 160 cases, among which are all the cases listed in the ISNA booklet "Last Will and Testament". Also tested are the famous Shafii, Shuraih, Ali, Omar and Abu-Bakr challenges.

You are welcome to copy and distribute the source code of this program to as many people as you like at no cost. It is not to be sold.

The IRTH program calculates inheritance portions due to heirs according to Islamic Law. The program screen displays heir categories, e.g., sons, daughters, ...etc. Simply, enter the number of heirs in each category in the two columns labeled "Number of heirs". If there are no heirs in a given category, enter 0 or leave the category blank. When the last category is entered, click the button labeled "Calculate". If you want to donate a part of your estate, not to exceed a third of it, to a person who is not an eligible heir, you can do so by clicking on "Preferences", and typing the bequest as a fraction of the estate, e.g., 1/4, before you click on "Calculate". The preferences section also allows you to specify your preferred juristic school.

The program was successfully tested using Internet Explorer versions 5.5 and above, Netscape Navigator versions 6.2 through 7.1, Mozilla version 1.4, America Online versions 6.0 through 9.0, Firefox, Chrome and Safari. It does not run under Netscape Navigator versions 4.5 or earlier, nor the Opera browser. It may or may not run on Windows 7. I recommend Firefox.

If you have any questions about the IRTH program, please send them to the address below. May God accept this work from me and turn it into a "knowledge that benefits."

Dr. Ayman Abu-Mostafa.

Contribute free Islamic software |  Back to the IRTH program


  1. "Fiqh-us-Sunna", Assayyed Sabeq, Darul Kitab-il Arabi, Beirut, Lebanon, Eigth Edition, 1987.
  2. Handbook of Last Will And Testament, Islamic Society of North America, Plainfield, Indiana, Second Edition, 1996.
  3. "Al-Mawareeth Ilman wa Amalan" (Inheritance theory and practice), Ahmad Ibrahim (Bek), Abdullah Wahba Bookstore, Cairo, Egypt, 1942.
  4. "Bahthun Mustafeedun Jamiun fi Mirath-il Ikhwati wal Jadd" (Extensive, comprehensive research in inheritance of siblings and grandfathers), Ahmad Ibrahim (Bek), Fathullah Ilyas Noori Bookstore, Egypt, 1938.

Revision history:

1989 Written in TurboPascal. Reviewed by Al-Azhar University, Egypt.
1990 Reviewed by Dr. Jamal Badawi.
1992 Ported to HyperTalk and reviewed by Dr. Jamal Badawi and others.
1998 Ported to JavaScript and reviewed by many.
2003 Extensively tested by Lubna Zubairi of the legacy department of Islamic Relief, London, U.K. Thank you.
Added preferences for juristic school and opinions.
Added relatives to mother ("Thowool-Arhaam") and bequests.
2005 Made easier to use for users of Firefox, Mozilla, Netscape Navigator and America Online browsers.
Added a page for frequently asked questions.
2007 Translated to Indonesian by Eko Suprapto Wibowo, Musthafa Zahir and Muhammad Abdul Mu'iz.