Is there evidence outside the Bible that Jesus existed?

Yes, in fact the historicity of Jesus is so overwhelming that no scholar of history even denies the fact that Jesus was a real person in real history.  The accounts range from Josephus, talking about Jesus’ miracles, His death, and resurrection (even though he casts doubts about it) to the Roman historian Tacitus, who gives a summary of Christ’s sentence and death under Emperor Tiberius and Pontus Pilate, and even the resurrection (again associating this part with a myth).  Even the Babylonian Talmud talks of Jesus and His miracles while on earth.  Only those who are militant against Christianity even dare try to deny that Jesus had a real place in history.  They are either uneducated in history or blind, or both.