King James Version (KJV) - Genesis 6:15 >

And this [is the fashion] which thou shalt make it [of:] The length of the ark [shall be] three hundred cubits, the breadth of it fifty cubits, and the height of it thirty cubits.

Berean Study Bible (BSB) - Genesis 6:15 >

And this is how you are to build it: The ark is to be 300 cubits long, 50 cubits wide, and 30 cubits high.