How many names does Allah actually have? There is alot of disagreement over this answer by various people.
As mentioned by our beloved Prophet (Sallalahu Alaihi Wassalam) in the hadith below, Allah has 99 names. One should note that these are actually attributes to the Almighty ie. the Creator, the Maker, the One, the Last etc.
The most supreme attributes can be found in the Quran eg. Surah Al-Fatiha: Al-Rahman and Al-Rahim. In Surah Ikhlass: Ahad and Samad.
The reason for the variation in numbers is that Allah the supreme has countless attributes, therefore the more research you do into this matter the more attributes you will find. Some scholars have recorded upto 4000 attributes/names to the divine.
At the very least one should memorise 99 names as mentioned by the teacher of all teachers (al-Muallim) Rasul-Allah (Sallalahu Alaihi Wassalam) and supplicate to the Almighty using these names for barakah.
“He is Allah, the Creator, the Originator, The Fashioner, to Him belong the most beautiful names: whatever is in the heavens and on earth, do declare His praises and glory. And He is the Exalted in Might, The Wise.”[Quran 59:24]“The most beautiful names belong to God: so call on Him by them..”[Quran 7:180]Allah’s Apostle (Sallalahu Alaihi Wassalam) said, “Allah has ninety-nine names, i.e. one-hundred minus one, and whoever knows them will go to Paradise.”[Sahih Al-Bukhari]