הלכה אויף יחזקאל 43:13

The measurements of the Altar are very exact and its shape is known [by tradition] from man to man. The altar that those who ascended from the [Babylonian] exile built was made like the one which will be built in the future. It is forbidden to add or subtract from its dimensions.

The Altar that Moses made, that Solomon made, that the returnees of the [First] Exile made, and that will be made in the future are all 10 cubits high, and that which is stated in the Torah: "and three cubits its height, that is the place of the pyre alone (above the ledge of the Altar). And the dimensions of the Altar that the returnees of the Exile made and the one that will be built in the future are 32 cubits by 32 cubits.