What was the biblical length of Noah’s Ark in Genesis?

The biblical length of Noah’s Ark in Genesis was 300 cubits.

Genesis 6:15 gives the Ark’s dimensions as 300 cubits long, 50 cubits wide, and 30 cubits high. A cubit was an ancient unit generally based on the length of a forearm, so its exact modern equivalent varies by historical period and culture.

Using a common estimate of about 45 centimetres per cubit, the Ark would be roughly 135 metres long. That conversion is approximate, not a measurement stated by Genesis itself. The text’s key point is the proportion: the Ark is described as a long, box-like vessel rather than a conventional sailing ship.

The biblical account also says the Ark had three decks, rooms or compartments, and a covering. Its stated purpose was preservation during the Flood, not navigation to a named port.