- Click Get key ↗ above (or go to
console.cloud.google.com) and sign in with a Google account.
- If you don't already have a project, click the project dropdown at the top of the page, then New Project. Give it any name and click Create — no credit card needed.
- Make sure that project is selected, then click Enable on the YouTube Data API v3 page.
- In the left-hand menu, click Credentials, then + Create Credentials → API key.
- Copy the key it gives you and paste it into the box above.
Free, and takes about five minutes. The default free tier is 10,000 quota units/day, which is plenty for regular use of this app. You only have to paste it once — it's saved in this browser, so you won't need to re-enter it next time.