Cross reference
Ezekiel 43:16
16 The altar hearth shall be twelve [cubits] long by twelve broad, square in the four sides of it.
Exodus 27:1
1 "You shall make the altar of acacia wood, five cubits long, and five cubits broad; the altar shall be foursquare: and its height shall be three cubits.
Exodus 38:1-2
1 He made the altar of burnt offering of acacia wood. It was square. Its length was five cubits, its breadth was five cubits, and its height was three cubits.
2 He made its horns on its four corners. Its horns were of one piece with it, and he overlaid it with brass.
2 Chronicles 4:1
1 Moreover he made an altar of brass, twenty cubits the length of it, and twenty cubits the breadth of it, and ten cubits the height of it.
Ezra 3:3
3 They set the altar on its base; for fear was on them because of the peoples of the countries: and they offered burnt offerings thereon to Yahweh, even burnt offerings morning and evening.