On what date did Noah enter the Ark at the start of the Flood, according to Genesis?

According to Genesis, Noah entered the Ark on the 17th day of the second month.

Genesis 7:11 places the beginning of the Flood in Noah’s six-hundredth year, on the seventeenth day of the second month. The passage says that on that day the fountains of the deep burst open and the windows of heaven opened. Genesis 7:13 then says Noah, his family, and the animals entered the ark on that same day.

The ancient calendar behind the wording is not identical to the modern Gregorian calendar. Biblical interpreters and traditions differ about how the months were reckoned, so the date should be retained in its scriptural form rather than converted to a modern date.

Genesis later gives another precise date: the ark came to rest on the mountains of Ararat on the seventeenth day of the seventh month. Those two seventeenth-day dates are easy to confuse, but they mark different stages of the story.