Exodus 27:1
"You are to build an altar of acacia wood. The altar must be square. It is to be 7 1/2 feet long, 7 1/2 feet wide, and 4 1/2 feet high.
Exodus 27:1, Readable English Bible (READ)
Note: Hebrew: 5 cubits long, 5 cubits wide, and 3 cubits high.