Where does “Álfr” come from?

Álfr (Old Norse) comes from Proto-Germanic albiz, from Proto-Indo-European albʰós — white.

Ancestry of “Álfr”, step by step

Step	Language	Word	Meaning
1	Proto-Germanic	albiz	elf, fairy
2	Proto-Indo-European	albʰós	white

Álfr — Etymology, Origin & Word History | Etymology Explorer