Incredibly, some dictionaries actually stoop to define “as per” as some sort of term or idiom.
Make no mistake: “As per” is a barbarism, an error, an ignorant gaffe. The error is committed by bureaucrats trying to sound official and by other self-important persons. These two words should never be written or spoken together.
“Per” means “as” or “according to.” It is a Latin preposition that is often translated into English as “as.” So you are free to say “per the instructions” or “as instructed” or “according to the instructions,” but you should never say “as per the instructions.” It is redundant usage and banal jargon to boot.
I hope this post, however short, is clear: Don’t ever use “as per.”