In Genesis, how many pairs of every kind of clean animal entered Noah's ark?

In Genesis, seven pairs of every kind of clean animal entered Noah’s ark.

Genesis 7:2 instructs Noah to take seven pairs of clean animals, male and female, while taking one pair of animals that are not clean. Genesis 7:3 separately gives seven pairs of birds. The passage therefore does not describe every animal as entering in exactly one pair.

This detail is often overlooked because the broad phrase “two by two” is a familiar summary of the story. Genesis 6:19–20 does use male-and-female pairs when first describing animals coming to the ark, while Genesis 7:2–3 provides the more detailed distinction between clean and unclean animals.

The category “clean” belongs to the ritual classification used in the biblical text. Genesis does not supply a complete species list, nor does it define the category there in the way later dietary laws do.