In Genesis, what is the traditional length of Noah's Ark in cubits?

In Genesis, the traditional length of Noah’s Ark is 300 cubits.

Genesis 6:15 gives the Ark’s dimensions as 300 cubits in length, 50 cubits in width, and 30 cubits in height. These figures are among the clearest numerical details in the account and establish a length-to-width-to-height ratio of 10:1:0.6.

A cubit was an ancient unit commonly based on the length of a forearm, but its exact standard varied by culture and period. For that reason, modern translations may add an approximate metric or imperial conversion, yet no single conversion is certain. Depending on the cubit used, 300 cubits is often estimated at roughly 135 to 157 meters.

The dimensions have also prompted naval and engineering discussions, especially because the long, box-like proportions are relatively stable even when the absolute measurement changes. Genesis does not claim that the Ark was built according to a modern ship design, nor does it provide evidence of a surviving vessel. The answer is the stated biblical measurement.