According to Genesis, what was the prescribed length of Noah’s Ark?

According to Genesis, the prescribed length of Noah’s Ark was 300 cubits.

Genesis 6:15 gives the Ark’s dimensions as 300 cubits long, 50 cubits wide, and 30 cubits high. Because the ancient cubit was based roughly on the length of a forearm, its exact modern equivalent is uncertain. Depending on the cubit used, 300 cubits is commonly estimated at roughly 135 to 157 metres, or about 443 to 515 feet.

The text therefore supplies a proportion more securely than a modern measurement. The Ark’s length-to-width-to-height ratio is 6:1:0.6, describing a large rectangular vessel rather than a ship designed for speed or navigation.

Modern reconstructions often choose a particular cubit length and then present a single metric figure, but those figures are interpretive. Genesis itself does not specify a modern unit or explain how the Ark was engineered. The length, 300 cubits, is the stable textual answer.