Q:

YouTube API Quota - Multiple accounts

Version 3 of the YouTube Data API has concrete quota numbers listed in the Google API Console where you register for your API Key. You can use 30,000 units/second/user and 1,000,000 per day. Projects that had enabled the YouTube Data API before April 20, 2016, have a default quota of 50M/day.

This means that once we breach this numbers, we'll receive in the header that the rate limits have been exceeded.
My question is, can you create multiple accounts, which will in theory DOUBLE the quota?
Or is it also IP restricted too meaning /user1/ & /user2/ requests won't actually change the quota?

A:

It is my understanding that the quota is PER PROJECT, not per account. You could create 3 projects and each project would have the default quota. Then in your application you could attempt to use all 3 combined in order to post to the API with a higher throughput.

