Praise be to Allah, and peace and blessings be upon the Messenger of Allah.
The time of a person’s death is part of the unseen knowledge that Allah, the Exalted, has kept exclusively for Himself. No one knows when or where they will die. Allah, the Exalted, says:
﴿وَعِندَهُ مَفَاتِحُ الْغَيْبِ لَا يَعْلَمُهَا إِلَّا هُوَ﴾ [الأنعام: 59]
“With Him are the keys of the unseen; none knows them except Him.” [Al-An‘am: 59]
Allah also says:
﴿إِنَّ اللَّهَ عِندَهُ عِلْمُ السَّاعَةِ وَيُنَزِّلُ الْغَيْثَ وَيَعْلَمُ مَا فِي الْأَرْحَامِ وَمَا تَدْرِي نَفْسٌ مَّاذَا تَكْسِبُ غَدًا وَمَا تَدْرِي نَفْسٌ بِأَيِّ أَرْضٍ تَمُوتُ﴾ [لقمان: 34]
“Indeed, Allah has knowledge of the Hour, sends down the rain, knows what is in the wombs, and no soul knows what it will earn tomorrow, nor does any soul know in what land it will die.” [Luqman: 34]
The Prophet ﷺ also explained that among the keys of the unseen, which are known only to Allah, are knowledge of what will happen tomorrow and knowledge of when and where a person will die.
Accordingly, it is not permissible to use such a test with the intention of knowing the time of a particular person’s death or asserting with certainty when they will die, because a person’s appointed term is part of the unseen, known only to Allah. Medical experiments or indicators cannot determine the exact time of death with certainty.
However, if the test is used for legitimate medical purposes, such as studying genetic predisposition to certain diseases or assessing health risks, without claiming knowledge of the time of death, then there is nothing wrong with using it for that purpose.
Therefore, it is prohibited to purchase, sell, or use the device if its purpose is to determine the time of a person’s death. It is permissible to use it for lawful medical purposes based on research and experimentation.
And Allah knows best.