The following are doubts that invalidate prayers: 1. a doubt about the number of rakʿahs performed in obligatory prayers consisting of two rakʿahs, such as ṣubḥ prayers and the prayer of a traveller. However, a doubt about the number of rakʿahs performed in recommended prayers and ṣalāt al‑iḥtiyāṭ does not invalidate them; 2. a doubt about the number of rakʿahs performed in prayers consisting of three rakʿahs; 3.
a doubt about whether one has performed one rakʿah or more in a prayer consisting of four rakʿahs; 4. in a prayer consisting of four rakʿahs, before going into the second sajdah, one doubts whether he has performed two rakʿahs or more; 5. a doubt about whether one has performed two or five rakʿahs, or, two or more than five rakʿahs; 6. a doubt about whether one has performed three or six rakʿahs, or, three or more than six rakʿahs; 7.
a doubt about the number of rakʿahs when one does not know at all how many rakʿahs he has performed; 8. a doubt about whether one has performed four or six rakʿahs, or four or more than six rakʿahs, as per the details that will be mentioned later.