For convenience and to suggest a celebration, we sometimes say that Janmastami is Krishna’s birthday, since anyone we know of on Earth, either past or present, is apparently “born” into this world. However, this is not an accurate description for Krishna (who we understand as the original feature of God), or for any of God’s other incarnations.
Why?
There is no “birth” or “death” for God, since by definition He is primeval, always existing, the source of everything, who has no material form with