According to Genesis, how long did the rain of Noah’s Flood fall on the Earth?

According to Genesis, the rain of Noah’s Flood fell for 40 days and 40 nights.

In the Genesis flood narrative, rain begins after Noah, his family, and the animals enter the ark. Genesis 7:12 uses the repeated phrase “forty days and forty nights,” a biblical expression that emphasizes a sustained period of rain and judgment. The text also says that floodwaters remained on the Earth for much longer than the rainfall itself.

This distinction is often missed. Genesis describes 40 days and nights of rain, but it says the waters prevailed for 150 days before beginning to recede. The story therefore does not present the entire flood as a 40-day event. “Forty” is also a recurring symbolic number in biblical literature, appearing in stories involving testing, preparation, or transition.

The flood account is part of Genesis chapters 6–9. Similar ancient Near Eastern flood stories, including the Epic of Gilgamesh, also describe prolonged catastrophic flooding, though their durations and details differ.