It’s conventionally taught that Allah has 99 names in Islam. However, the list of these names was compiled–or rather invented–by followers of Muhammad after Muhammad made this declaration. In the Quran, names for Allah develop very slowly. In fact, “Allah” itself was likely not used as a name of Allah until Surah 7–the earlier rare references to “Allah” seem to be later additions, which were added to make the early surat compatible with the developing theology of Islam.
This article will expand as I work my way through the Quran.
In Surah 96:1-5, the only title used for Allah is Rabbi, the Lord. (“Most generous” is just an adjective, not a name.) Muhammad is directed to the name He-Who-Created, but he misses it.
This is also the only title of Surah 74:1-5. There is no name at all used in Surah 81 until the late addition of the last ayah–the “Owner” of the Throne is just a possessive particle. In Surah 87, again, uses only Rabbi (and He-Who-Created) until “Allah” is added in an ayah of a considerably later date.