What is the minimum YouTube video length for monetization ?

Hi,
What is the minimum YouTube video length for monetization ? At least how many minutes should video have to be monetized ?

There is no minimum video length for monetization. So your video can be monetized if it has only a few seconds, a couple of minutes or hours.

But for optimal revenue purpose, the video should have at least 8 minutes. If you video has 8 minutes or more, you can place extra mid-role ads into it.