Assalaamu alaykum wa rahmatullaahi wa barakaatuhu. I often forget how many times I have recited each of the three Quls in the Athkaar (expressions of remembrance of Allah) of the morning and the evening. So how can I complete those then? Should I take the smaller possible number? Sometimes,I have no idea about the number.

All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ʻalayhi wa sallam, is His slave and Messenger.

If you doubt the number of times you have recited the Athkaar, then you should take the smaller number in order to be on the safe side. So if you doubt whether you recited Soorahs Al-Ikhlaas, Al-Falaq, and An-Naas (or the three Quls as you referred to them) twice or thrice, you should act on the basis that you recited them only twice. Likewise, if you do not know the number, you should choose the smallest number to be on the safe side until you believe that you have most likely recited the required number of times.

Al-Khateeb Ash-Shirbeeni wrote, “When one has doubts, he should act upon the least number which he is certain of. This is obligatory when performing obligatory acts of worship and recommended when performing Sunnah acts of worship, because the basic principle is that no additional times were performed. For instance, if a person doubts the number of units of prayer which he has prayed or whether he has washed a part of his body thrice or twice (in ablution), he should act upon what is certain, which is the smaller number.” [Mughni Al-Muhtaaj]

Allah knows best.