How old was Jesus during the "flight into Egypt"?

If we assume that Herod and the magi were accurate in their calculations of the Christmas star’s first appearance, that would mean Jesus was no older than two years.

When Herod realized that he had been deceived by the magi, he became furious. He ordered the massacre of all the boys in Bethlehem and its vicinity two years old and under, in accordance with the time he had ascertained from the magi (Matt. 2:26).