How do you know your God exists?

Because only the God I worship has fulfilled hundreds of prophecies, gave us historical evidence, and actually transforms lives. I know my God is true because once I accepted him, I received the Holy Spirit. God has shown me miracles and revealed himself. I asked and I received. After all that he has already done for me, how could I possibly deny his existence? When he is working in my life every single day, it would be absurd to deny that he is real.